Provided by: remind_03.04.01-1_amd64 bug

NAME

       remind - a sophisticated reminder service

SYNOPSIS

       remind [options] filename [date] [*rep] [time]

DESCRIPTION

       Remind  reads  the  supplied filename and executes the commands found in it.  The commands
       are used to issue reminders and alarms.  Each reminder or alarm can consist of  a  message
       sent to standard output, or a program to be executed.

       If  filename  is specified as a single dash '-', then Remind takes its input from standard
       input.  This also implicitly enables the -o option, described below.

       If filename happens to be a directory rather than a plain file, then Remind reads  all  of
       the  files in that directory that match the pattern "*.rem".  The files are read in sorted
       order; the sort order may depend on your locale, but should match the sort order  used  by
       the shell to expand "*.rem".

       Remind  reads  its  files starting from the beginning to the end, or until it encounters a
       line whose sole content is "__EOF__" (without the quotes.)   Anything  after  the  __EOF__
       marker is completely ignored.

OPTIONS

       Remind  has a slew of options.  If you're new to the program, ignore them for now and skip
       to the section "REMINDER FILES".

       -n     The -n option causes Remind to print the next occurrence  of  each  reminder  in  a
              simple  calendar  format.   You  can sort this by date by piping the output through
              sort(1).  Note that the -n option causes any -g option to be ignored.

       -j[n]  Runs Remind in "purge" mode to get rid of expired reminders.  See the section PURGE
              MODE for details.

       -r     The -r option disables RUN directives and the shell() function.

       -c[flags]n
              The  -c option causes Remind to produce a calendar that is sent to standard output.
              If you supply a number n, then a calendar will be generated for n months,  starting
              with  the  current  month.   By  default,  a calendar for only the current month is
              produced.

              You can precede n (if any) with a set of flags.  The flags are as follows:

              '+'    causes a calendar for n weeks to be produced.

              'a'    causes Remind to display reminders on the calendar on the day they  actually
                     occur as well as on any preceding days specified by the reminder's delta.

              'l'    causes  Remind  to  use  VT100 line-drawing characters to draw the calendar.
                     The characters are hard-coded and will only work on terminals  that  emulate
                     the VT00 line-drawing character set.

              'u'    is  similar to 'l', but causes Remind to use UNICODE line-drawing characters
                     to draw the calendar.  The characters are hard-coded and will only  work  on
                     terminals that are set to UTF-8 character encoding.

              'c'    causes  Remind  to  use  VT100 escape sequences to approximate SPECIAL COLOR
                     reminders.  Note that this flag is  kept  for  backwards-compatibility;  you
                     should use the -@[n][,m] command-line option instead.

       -@[n][,m]
              Tells  Remind  to approximate SPECIAL COLOR reminders using VT100 escape sequences.
              The approximation is (of necessity) very coarse, because the VT100 only  has  eight
              different  color  sequences,  each with one of two brightnesses.  A color component
              greater than 64 is considered "on", and if any of the  three  color  components  is
              greater than 128, the color is considered "bright".

              If  you  supply  the  optional numeric parameters, the have the following meanings:
              n=0 tells Remind to use the standard 16 VT100 colors.   n=1  tells  it  to  use  an
              extended 256-color palette supported by many terminal emulators such as xterm.  And
              n=2 tells it to use  escape  sequences  that  support  true  24-bit  colors,  again
              supported by many terminal emulators such as xterm.

              If  the  optional  m parameter is supplied following a comma, then m=0 tells Remind
              that the terminal background is dark, and Remind will brighten up  dark  colors  to
              make  them  visible.   If m=1, then Remind assumes the terminal background is light
              and it will darken bright colors to make them visible.  If no m is  supplied,  then
              Remind  does  not  perform  any  adjustments,  and  some  reminders  may be hard or
              impossible to see if the color is too close to the terminal background color.

       -wcol[,pad[,spc]]]
              The -w option specifies the output width, padding  and  spacing  of  the  formatted
              calendar output.  Col specifies the number of columns in the output device.  If not
              specified, or specified as 0, it defaults to the larger of 71 or the  actual  width
              of your terminal, or to 80 if standard output is not a terminal.

              Pad  specifies  how many lines to use to "pad" empty calendar boxes.  This defaults
              to 5.  If you have many reminders on certain days that make your calendar too large
              to  fit  on  a page, you can try reducing pad to make the empty boxes smaller.  Spc
              specifies how many blank lines to leave  between  the  day  number  and  the  first
              reminder entry.  It defaults to 1.

              Any  of col, pad or spc can be omitted, providing you provide the correct number of
              commas.  Don't use any spaces in the option.

       -s[a]n The -s option is very similar to the -c option, except that the output calendar  is
              not  formatted.   It  is  listed in a "simple format" that can be used as input for
              more sophisticated calendar-drawing programs.  If n starts with  "+",  then  it  is
              interpreted as a number of weeks.

              If  you  immediately follow the s with the letter a, then Remind displays reminders
              on the calendar on the day they actually occur as well as  on  any  preceding  days
              specified by the reminder's delta.

       -p[a][p][p]n
              The  -p  option  is  very similar to the -s option, except that the output contains
              additional information for use by the Rem2PS program, which  creates  a  PostScript
              calendar,  and  various  other  back-end programs.  For this option, n cannot start
              with "+"; it must specify a number of months.  The  format  of  the  -p  output  is
              described  in  the  rem2ps(1)  man  page.  If you immediately follow the p with the
              letter a, then Remind displays reminders on the calendar on the day  they  actually
              occur  as  well as on any preceding days specified by the reminder's delta.  If you
              follow the p with another p, then  Remind  uses  a  more  comprehensive  JSON-based
              format rather than the "simple calendar" format.  This format is also documented in
              the rem2ps(1) man page.  Finally, if you use three p's, as  in  -ppp,  then  Remind
              uses a pure JSON format, again documented in rem2ps(1).

              Note that the -pp or -ppp options also enable the -l option.

       -l     If  you  use  the  -l option in conjunction with the -p option, then Remind outputs
              additional information for back-end  programs  such  as  rem2ps.   This  additional
              information  lets  the  back-end programs correlate a reminder with the source file
              and line number that produced it.

       -m     The -m option causes the -c or -p options to produce a calendar whose first  column
              is Monday rather than Sunday.  (This conforms to the international standard.)

       -v     The  -v  option  makes the output of Remind slightly more verbose.  Currently, this
              causes Remind to echo a bad line in case of an  error,  and  to  print  a  security
              message if a script tests the $RunOff system variable.

       -o     The -o option causes Remind to ignore all ONCE directives.

       -t     The -t option causes Remind to trigger all non-expired reminders, regardless of the
              delta supplied for each reminder.

       -tn    If you supply a number n after the -t option, then Remind pretends that  each  non-
              expired reminder has a delta of n days and triggers reminders accordingly.

       -tt[n] The  -tt  option causes Remind to assume a default delta of n minutes for all timed
              reminders.  If -tt is given with no n, a default delta of 5 minutes is used.

       -h     The -h option ("hush...") suppresses certain warning and information messages.   In
              particular, if no reminders are triggered, this mode produces no output.

       -a     The -a option causes Remind not to immediately trigger timed reminders that trigger
              on the current day.  It also causes Remind  not  to  place  timed  reminders  in  a
              calendar.   If  you  supply  two or more -a options, then Remind will trigger timed
              reminders that are in the future, but will not trigger timed reminders  whose  time
              has passed.  (Regardless of how many -a options you supply, Remind will not include
              timed reminders in the calendar if at least one -a option is used.)

       -q     The -q option causes Remind not to queue timed reminders for later execution.

       -f     The -f option causes Remind to remain in  the  foreground  when  processing  queued
              reminders, rather than forking off a background process to handle them.

       -e     The  -e  option diverts error messages (normally sent to the standard error stream)
              to the standard output stream.

       -dchars
              The -d option enables certain debugging modes.  The chars specify  which  modes  to
              enable:

         e      Echo all input lines

         x      Trace all expression evaluation

         t      Display all trigger date computation

         v      Dump the variable table after execution of the reminder script

         l      Echo lines when displaying error messages

         f      Trace the reading of reminder files

       -g[a|d[a|d[a|d[a|d]]]]
              Normally,  reminders  are  issued in the order in which they are encountered in the
              reminder script.  The -g option cause Remind to sort reminders  by  date  and  time
              prior  to  issuing  them.   The  optional a and d characters specify the sort order
              (ascending or descending) for the date, time and priority fields.  See the  section
              "SORTING REMINDERS" for more information.

              Note that -g is ignored if you use the -n option.

       -b[n]  Set the time format for the calendar and simple-calendar outputs.  N can range from
              0 to 2, with the default 0.  A value of 0 causes times to be  inserted  in  12-hour
              (am/pm)  format.   1  causes times to be inserted in 24-hour format, and 2 inhibits
              the automatic insertion of times in the calendar output.

       -x[n]  Sets the iteration limit for the SATISFY clause of a REM command.  Defaults to 150.

       -kcmd  Instead of simply printing MSG-type reminders, this causes them to be passed to the
              specific cmd.  You must use '%s' where you want the body to appear, and may need to
              enclose this option in quotes.  Note that all shell characters in the body  of  the
              reminder  are  escaped  with  a  backslash,  and the entire body of the reminder is
              passed as a single argument.  Note that this option overrides the -r option and the
              RUN OFF command.

              As  an example, suppose you have an X Window program called xmessage that pops up a
              window and displays its invocation arguments.  You could use:

                        remind '-kxmessage %s &' ...

              to have all of your MSG-type reminders processed using xmessage.

              A word of warning: It is very easy to spawn dozens of xmessage processes  with  the
              above  technique.  So be very careful.  Because all shell and whitespace characters
              are escaped, the program you execute with the -k option must be prepared to  handle
              the entire message as a single argument.

       -z[n] Runs Remind in the daemon mode.  If n
              is  supplied, it specifies how often (in minutes) Remind should wake up to check if
              the reminder script has been changed.  N defaults to 1, and can range from 1 to 60.
              Note that the use of the -z option also enables the -f option.

              If  you  supply  the  option -z0, Remind runs in a special mode called server mode.
              This is documented in the tkremind man page; see tkremind(1).

       -uname Runs Remind with the uid and gid of the user specified by name.  The option changes
              the  uid  and  gid as described, and sets the environment variables HOME, SHELL and
              USER to the home directory, shell, and user name, respectively,  of  the  specified
              user.   LOGNAME  is  also set to the specified user name.  This option is meant for
              use in shell scripts that mail reminders to all users.   Note  that  as  of  Remind
              3.00.17,  using  -u  implies  -r  --  the  RUN  directive and shell() functions are
              disabled.  However, if you prefix name with a +-sign, then RUN and shell() are  not
              disabled.   That  is,  -uwhatever  switches  the user to whatever and disables RUN,
              whereas -u+whatever switches the user to whatever but leaves RUN enabled.

              Non-root users can also use the -u option.  However, in this case, it only  changes
              the environment variables as described above.  It does not change the effective uid
              or gid.

       -+username
              Causes Remind to trust files owned by the user username.  Normally, if Remind reads
              a  file that you do not own, it disables RUN and the shell() function.  This option
              causes it to also trust files owned  by  username.   You  can  supply  multiple  -+
              options to trust multiple users, up to a limit of 20 trusted users.

       -y     Causes Remind to synthesize a tag for any reminder that lacks a TAG clause.

       -ivar=expr
              Sets  the  value  of the specified var to expr, and preserves var.  Expr can be any
              valid Remind expression.  See the section "INITIALIZING VARIABLES  ON  THE  COMMAND
              LINE" for more details.

       -ifunc(args)=definition
              Allows you to define a function on the command line.

       If  you supply a date on the command line, it must consist of day month year, where day is
       the day of the month, month is at least the first three letters of the English name of the
       month,  and  year is a year (all 4 digits) from 1990 to about 2075.  You can leave out the
       day, which then defaults to 1.

       If you do supply a date on the command line, then Remind uses it, rather than  the  actual
       system  date, as its notion of "today."  This lets you create calendars for future months,
       or test to see how your reminders will be triggered in the  future.   Similarly,  you  can
       supply  a  time to set Remind's notion of "now" to a particular time.  Supplying a time on
       the command line also implicitly enables the -q option and disables the  -z  option.   The
       time may be specified in 24-hour format (eg, 13:20) or common "AM/PM" format (1:20pm).

       If  you  would rather specify the date more succinctly, you can supply it as YYYY-MM-DD or
       YYYY/MM/DD.  You can even supply a date and time on the  command  line  as  one  argument:
       YYYY-MM-DD@HH:MM.

       In  addition,  you  can  supply  a repeat parameter, which has the form *rep.  This causes
       Remind to be run rep times, with the date incrementing on each iteration.  You may have to
       enclose  the  parameter  in quotes to avoid shell expansion.  See the subsection "Repeated
       Execution" in the section "CALENDAR MODE" for more information.

REMINDER FILES

       Remind uses scripts to control its operation.  You can use  any  text  editor  capable  of
       creating  plain  ASCII  files to create a Remind script.  The commands inside a script can
       range from the very simple and almost immediately understandable:

            REM 6 Jan MSG Dianne's birthday

       to the baroque and obscure:

            REM [date(thisyear, 1, 1) + 180] ++5 OMIT \
            sat sun BEFORE MSG [ord(thisyear-1980)] payment due %b!

       A reminder file consists of commands, with one command per line.   Several  lines  can  be
       continued  using  the  backslash character, as in the above example.  In this case, all of
       the concatenated lines are treated as a single line by Remind.   Note  that  if  an  error
       occurs, Remind reports the line number of the last line of a continued line.

       Remind  ignores  blank lines, and lines beginning with the '#' or ';' characters.  You can
       use the semicolon as a comment character if you wish to pass a Remind script through the C
       pre-processor,  which  interprets  the  '#'  character  as  the  start of a pre-processing
       directive.

       Note that Remind processes line continuations before anything else.  For example:

            # This is a comment \
            This line is part of the comment because of line continuation \
            and so on.
            REM MSG This line is not ignored (no \ above)

       Remind is not case sensitive; you can generally use any mixture of  upper-  or  lower-case
       for commands, parameters, invocation options, etc.

THE REM COMMAND

       The  most  powerful  command  in  a  Remind  script  is  the REM command.  This command is
       responsible for issuing reminders.  Its syntax is:

              REM [ONCE] [date_spec] [back] [delta] [repeat] [PRIORITY prio]  [SKIP  |  BEFORE  |
              AFTER]  [OMIT  omit_list]  [ADDOMIT]  [OMITFUNC  omit_function]  [AT  time [tdelta]
              [trepeat]] [SCHED sched_function] [WARN warn_function] [UNTIL expiry_date | THROUGH
              last_date]  [SCANFROM  scan_date  |  FROM start_date] [DURATION duration] [TAG tag]
              <MSG | MSF | RUN | CAL | SATISFY | SPECIAL special | PS | PSFILE> body

       The parts of the REM command can be specified in any order, except that the body must come
       immediately after the MSG, RUN, CAL, PS, PSFILE or SATISFY keyword.

       The  REM token is optional, providing that the remainder of the command cannot be mistaken
       for another Remind command such as OMIT or RUN.  The portion of the REM command before the
       MSG, MSF RUN, CAL or SATISFY clause is called a trigger.

       MSG, MSF, RUN, CAL, SPECIAL, PS and PSFILE

       These  keywords denote the type of the reminder.  (SATISFY is more complicated and will be
       explained later.)  A MSG-type reminder normally prints a message to the  standard  output,
       after  passing  the  body  through a special substitution filter, described in the section
       "THE SUBSTITUTION FILTER."  However, if you have used the  -k  command-line  option,  then
       MSG-type  reminders  are passed to the appropriate program.  Note that the options -c, -s,
       -p and -n disable the -k option.

       Note that you can omit the reminder type, in which case it defaults to MSG.   So  you  can
       write:

            6 January Dianne's Birthday

       although this is not recommended.

       The  MSF  keyword  is  almost  the  same  as  the MSG keyword, except that the reminder is
       formatted to fit into  a  paragraph-like  format.   Three  system  variables  control  the
       formatting  of  MSF-type  reminders  -  they are $FirstIndent, $SubsIndent and $FormWidth.
       They are discussed in the section "SYSTEM VARIABLES."  The MSF keyword causes the  spacing
       of  your  reminder  to  be altered - extra spaces are discarded, and two spaces are placed
       after periods and other characters, as specified by  the  system  variables  $EndSent  and
       $EndSentIg.   Note  that  if  the body of the reminder includes newline characters (placed
       there with the %_ sequence), then the newlines  are  treated  as  the  beginnings  of  new
       paragraphs,  and  the $FirstIndent indentation is used for the next line.  You can use two
       consecutive newlines to have spaced paragraphs emitted from a single reminder body.

       A RUN-type reminder also passes  the  body  through  the  substitution  filter,  but  then
       executes  the  result  as  a  system  command.   A CAL-type reminder is used only to place
       entries in the calendar produced when Remind is run with the -c, -s or -p options.

       A PS or PSFILE-type reminder is used to pass PostScript code directly to the printer  when
       producing  PostScript  calendars.  This can be used to shade certain calendar entries (see
       the psshade() function), include graphics in the calendar, or almost any other purpose you
       can  think  of.   You  should  not  use  these types of reminders unless you are an expert
       PostScript programmer.  The PS and PSFILE reminders are ignored unless Remind is run  with
       the -p option.  See the section "More about PostScript" for more details.

       A  SPECIAL-type  reminder  is  used  to  pass  "out-of-band"  information from Remind to a
       calendar-producing back-end.  It should be followed by  a  word  indicating  the  type  of
       special  data  being passed.  The type of a special reminder depends on the back-end.  For
       the Rem2PS back-end, SPECIAL PostScript is equivalent to a PS-type reminder,  and  SPECIAL
       PSFile  is  equivalent  to  a  PSFILE-type  reminder.   The  body of a SPECIAL reminder is
       obviously dependent upon the back-end.  A back-end must ignore a SPECIAL that it does  not
       recognize.

       DATE SPECIFICATIONS

       A  date_spec  consists  of  zero to four parts.  These parts are day (day of month), month
       (month name), year and weekday.  Month and weekday are the English  names  of  months  and
       weekdays.   At  least the first three characters must be used.  The following are examples
       of the various parts of a date_spec:

       day:   1, 22, 31, 14, 3

       month: JANUARY, feb, March, ApR, may, Aug

       year:  1990, 1993, 2030.  The year can range from 1990 to 2075.

       weekday:
              Monday, tue, Wed, THU, Friday, saturday, sundAy

       Note that there can be several weekday components separated by spaces in a date_spec.

       INTERPRETATION OF DATE SPECIFICATIONS

       The following examples show how date specifications are interpreted.

       1. Null date specification - the reminder is triggered every day.  The trigger date for  a
       specific run is simply the current system date.

       2.  Only  day present.  The reminder is triggered on the specified day of each month.  The
       trigger date for a particular run is the closest such day to the current system date.  For
       example:
            REM 1 MSG First of every month.
            REM 31 MSG 31st of every month that has 31 days.

       3.  Only  month  present.   The  reminder  is  triggered every day of the specified month.
       Example:
            REM Feb MSG Every day in February

       4.  day and month present.  Examples:
            REM 6 Jan MSG Every 6th of January
            REM Feb 29 MSG Every 29th of February

       5.  Only year present. Example:
            REM 1991 MSG Every day in 1991

       6.  year and day present.  Examples:
            REM 1 1990 MSG 1st of every month in 1990
            REM 1992 23 MSG 23rd of every month in 1992

       7.  year and month present.  Examples:
            REM Feb 1991 MSG Every day in Feb 1991
            REM 1992 September MSG Every day in Sept 1992

       8.  year, month and day present.  Examples:
            REM 8 Jan 1991 MSG 8th January 1991.
            REM 1992 March 9 MSG 9th March 1992.

       9.  weekday only.  Examples:
            REM Sat MSG Every Saturday
            REM Mon Tue Wed Thu Fri MSG Every working day
            REM Monday Wednesday MSG Every Monday and Wednesday

       10.  weekday and day present.  Examples:
            REM Sat 1 MSG First Saturday of every month
            REM Mon Tue Wed Thu Fri 15 \
                 MSG 1st working day on or after 15th of every month

       11.  weekday and month present.  Examples:
            REM Mon March MSG Every Monday in March
            REM Mon Tue Wed Thu Fri Feb MSG Every working day in February

       12.  weekday, month and day present.  Examples:
            REM Mon 1 March MSG First Monday in March
            REM Sat Sun 15 July MSG First Sat or Sun on or after 15 July

       13.  weekday and year present.  Example:
            REM Sat Sun 1991 MSG Every Saturday and Sunday in 1991

       14.  weekday, day and year present.  Examples:
            REM Mon 15 1990 MSG 1st Mon after 15th of every month in 1990
            REM Mon Tue Wed Thu Fri 1 1990 \
                 MSG 1st working day of every month in 1990

       15.  weekday, month and year present.  Example:
            REM Mon Wed 1991 Feb MSG Every Mon and Wed in Feb 1991.

       16.  weekday, day, month and year present.  Example:
            REM Mon Tue Wed Thu Fri 28 Oct 1990 \
                 MSG 1st working day on or after 28 October 1990.

       Note that when both weekday and day are specified, Remind chooses the  first  date  on  or
       after  the  specified  day  that  also  satisfies the weekday constraint.  It does this by
       picking the first date on or after the specified  day  that  is  listed  in  the  list  of
       weekdays.  Thus, a reminder like:

            REM Mon Tue 28 Oct 1990 MSG Hi

       would  be  issued only on Monday, 29 October, 1990.  It would not be issued on Tuesday, 30
       October, 1990, since the 29th is the first date to satisfy the weekday constraints.

       SHORT-HAND DATE SPECIFICATIONS

       In addition to spelling out the day, month and year separately, you can specify YYYY-MM-DD
       or YYYY/MM/DD.  For example, the following statements are equivalent:

            REM 5 June 2010 MSG Cool!
            REM 2010-06-05  MSG Cool!

       You  can  also  specify  a  date  and  time  as  YYYY-MM-DD@HH:MM.   These  statements are
       equivalent:

            REM 19 Dec 2010 AT 16:45 MSG Hi
            REM 2010-12-19@16:45 MSG Hi

       There's one subtlety with short-hand date specifications:  The  following  statements  are
       not equivalent:

            REM 19 Dec 2010 AT 16:45 +60 MSG Hi
            REM 2010-12-19@16:45 +60 MSG Hi

       In  the  second  statement,  the  "+60"  is a delta that applies to the date rather than a
       tdelta that applies to the time.  We recommend explicitly using the AT keyword with  timed
       reminders.

       THE REMIND ALGORITHM

       Remind  uses  the following algorithm to compute a trigger date: Starting from the current
       date, it examines each day, one at a time, until it finds a date that satisfies  the  date
       specification,  or  proves  to  itself that no such date exists.  (Actually, Remind merely
       behaves as if it used this algorithm; it would be much too slow in practice.   Internally,
       Remind  uses  much  faster  techniques  to  calculate  a trigger date.)  See DETAILS ABOUT
       TRIGGER COMPUTATION for more information.

       BACKWARD SCANNING

       Sometimes, it is necessary to specify a date as being a set amount of time before  another
       date.   For  example,  the last Monday in a given month is computed as the first Monday in
       the next month, minus 7 days.  The back specification in the  reminder  is  used  in  this
       case:

            REM Mon 1 -7 MSG Last Monday of every month.

       A  back is specified with one or two dashes followed by an integer.  This causes Remind to
       move "backwards" from what would normally be the trigger date.  The difference between --7
       and -7 will be explained when the OMIT keyword is described.

       ADVANCE WARNING

       For  some  reminders,  it  is  appropriate  to  receive advance warning of the event.  For
       example, you may wish to be reminded of someone's birthday several days in  advance.   The
       delta  portion  of the REM command achieves this.  It is specified as one or two "+" signs
       followed by a number n.  Again, the difference between the "+"  and  "++"  forms  will  be
       explained  under  the  OMIT keyword.  Remind will trigger the reminder on computed trigger
       date, as well as on each of the n days before the event.  Here are some examples:

            REM 6 Jan +5 MSG Remind me of birthday 5 days in advance.

       The above example would be triggered every 6th of January, as well as the 1st through  5th
       of January.

       PERIODIC REMINDERS

       We  have  already  seen  some built-in mechanisms for certain types of periodic reminders.
       For example, an event occurring every Wednesday could be specified as:

            REM Wed MSG Event!

       However, events that do not repeat  daily,  weekly,  monthly  or  yearly  require  another
       approach.   The  repeat component of the REM command fills this need.  To use it, you must
       completely specify a date (year, month and  day,  and  optionally  weekday.)   The  repeat
       component is an asterisk followed by a number specifying the repetition period in days.

       For  example,  suppose  you  get  paid  every  second  Wednesday, and your last payday was
       Wednesday, 28 October, 1992.  You can use:

            REM 28 Oct 1992 *14 MSG Payday

       This issues the reminder every 14 days, starting from the calculated  trigger  date.   You
       can  use delta and back with repeat.  Note, however, that the back is used only to compute
       the initial trigger date; thereafter, the reminder  repeats  with  the  specified  period.
       Similarly,  if  you  specify a weekday, it is used only to calculate the initial date, and
       does not affect the repetition period.

       SCANFROM and FROM

       The SCANFROM and FROM keywords are for advanced  Remind  programmers  only,  and  will  be
       explained  in the section "DETAILS ABOUT TRIGGER COMPUTATION" near the end of this manual.
       Note that SCANFROM is available only in versions of Remind  from  03.00.04  up.   FROM  is
       available only from 03.01.00 and later.

       PRIORITY

       The  PRIORITY keyword must be followed by a number from 0 to 9999.  It is used in calendar
       mode and when sorting reminders.  If two reminders have the same trigger  date  and  time,
       then  they  are  sorted  by  priority.  If the PRIORITY keyword is not supplied, a default
       priority of 5000 is used.  (This default can be changed by adjusting the  system  variable
       $DefaultPrio.  See the section "SYSTEM VARIABLES" for more information.)

       EXPIRY DATES

       Some  reminders  should  be  issued periodically for a certain time, but then expire.  For
       example, suppose you have a class every Friday, and that your last class is on 11 December
       1992.  You can use:

            REM Fri UNTIL 11 Dec 1992 MSG Class today.

       Another  example:  Suppose you have jury duty from 30 November 1992 until 4 December 1992.
       The following reminder will issue the message every day of your jury duty, as  well  as  2
       days ahead of time:

            REM 1992-11-30 *1 +2 UNTIL 1992-12-04 MSG Jury duty

       Note  that the repeat of *1 is necessary; without it, the reminder would be issued only on
       30 November (and the two days preceding.)

       As a special case, you can use the THROUGH keyword instead of *1 and UNTIL.  The following
       two REM commands are equivalent:

            REM 1992-11-30 *1 +2 UNTIL 1992-12-04 MSG Jury duty

            REM 1992-11-30 +2 THROUGH 1992-12-04 MSG Jury duty

       If you have an expiry date via the use of THROUGH or UNTIL, then Remind will never trigger
       the reminder after the expiry date.  For example, if you have this:

               OMIT 2021-01-08
               REM 2021-01-01 THROUGH 2021-01-08 AFTER MSG Test

       the reminder will not be triggered  on  2021-01-08,  and  nor  will  it  be  triggered  on
       2021-01-09;  even  though  the AFTER keyword would normally move the 8th's reminder to the
       9th, the expiry date of 2021-01-08 overrides that.

       THE ONCE KEYWORD

       Sometimes, it is necessary to ensure that reminders are run only once on a given day.  For
       example, if you have a reminder that makes a backup of your files every Friday:

            REM Fri RUN do_backup

       (Here,  do_backup  is assumed to be a program or shell script that does the work.)  If you
       run Remind from your .login script, for example, and log in several  times  per  day,  the
       do_backup program will be run each time you log in.  If, however, you use the ONCE keyword
       in the reminder, the Remind checks the last access date of the reminder script.  If it  is
       the  same  as  the current date, Remind assumes that it has already been run, and will not
       issue reminders containing the ONCE keyword.

       Note that if you view or edit your reminder script, the last access date will be  updated,
       and  the  ONCE keyword will not operate properly.  If you start Remind with the -o option,
       then the ONCE keyword will be ignored.

       LOCALLY OMITTING WEEKDAYS

       The OMIT portion of the REM command is used to "omit" certain days when counting the delta
       or  back.   It  is  specified  using the keyword OMIT followed by a list of weekdays.  Its
       action is best illustrated with examples:

            REM 1 +1 OMIT Sat Sun MSG Important Event

       This reminder is normally triggered on the first of  every  month,  as  well  as  the  day
       preceding  it.   However,  if the first of the month falls on a Sunday or Monday, then the
       reminder is triggered starting from the previous Friday.  This is because the delta of  +1
       does  not  count  Saturday  or  Sunday  when  it counts backwards from the trigger date to
       determine how much advance warning to give.

       Contrast this with the use of "++1" in the above command.  In this case, the  reminder  is
       triggered  on  the first of each month, as well as the day preceding it.  The omitted days
       are counted.

            REM 1 -1 OMIT Sat Sun MSG Last working day of month

       Again, in the above example, the back of -1 normally causes the trigger  date  to  be  the
       last  day  of  the  month.  However, because of the OMIT clause, if the first of the month
       falls on a Sunday or Monday, the trigger date is  moved  backwards  past  the  weekend  to
       Friday.   (If  you  have  globally  omitted holidays, the reminder will be moved back past
       them, also.  See "The OMIT command" for more details.)

       By comparison, if we had used "--1", the reminder would be triggered on the  last  day  of
       the month, regardless of the OMIT.

       COMPUTED LOCAL OMITS

       The  OMITFUNC  phrase  of  the REM command allows you to supply a function that determines
       whether or not a date is omitted.  The function is passed a single parameter of type DATE,
       and  must  return  a non-zero integer if the date is considered "omitted" and 0 otherwise.
       Here's an example:

               FSET _third(x) (day(x) % 3) || \
                              (wkdaynum(x) == 0) || \
                              (wkdaynum(x) == 6)
               REM OMITFUNC _third AFTER MSG Working day divisible by 3

       In the example above, the reminder is triggered every Monday to Friday whose  day-of-month
       number is divisible by three.  Here's how it works:

       o      The OMITFUNC _third portion causes all days for which _third(x) returns non-zero to
              be considered "omitted".  This causes all days whose day-of-month number is  not  a
              multiple  of  three  to  be omitted.  Note that _third also returns non-zero if the
              weekday is Sunday or Saturday.

       o      The AFTER keyword causes the reminder to be moved after a block of omitted days.

       The combination of OMITFUNC and AFTER keyword causes the reminder to be issued on all days
       whose day-of-month number is divisible by three, but not on Saturday or Sunday.

       Note  that  if you use OMITFUNC, then a local OMIT is ignored as are all global OMITs.  If
       you want to omit specific weekdays,  your  omit  function  will  need  to  test  for  them
       specifically.   If  you  want to take into account the global OMIT context, then your omit
       function will need to test for that explicitly (using the isomitted() function.)

       Note that an incorrect OMITFUNC might cause all days to be considered omitted.   For  that
       reason,  when  Remind  searches  through  omitted days, it terminates the search after the
       SATISFY iteration limit (command-line option -x.)

       ADDING TRIGGER DATES TO THE OMIT CONTEXT

       If the ADDOMIT keyword appears in a REM command, then the trigger date (if  one  could  be
       calculated) is automatically added to the list of global OMITs.

       The command:

               REM ... whatever ... ADDOMIT MSG Foo

       is identical in behaviour to the sequence:

               REM ... whatever ... SATISFY 1
               IF trigvalid()
                   OMIT [trigdate()] MSG Foo
               ENDIF

       TIMED REMINDERS

       Timed  reminders  are those that have an AT keyword followed by a time and optional tdelta
       and trepeat.  The time  may  be  specified  in  24-hour  format,  with  0:00  representing
       midnight,  12:00  representing  noon,  and  23:59  representing  one  minute  to midnight.
       Alternatively, it may be specified in common "AM/PM" format; in this case, the  hour  must
       range  from  1  to  12.  12:00am represents midnight, 12:00pm represents noon, and 11:59pm
       represents one minute to midnight.  The "am" and "pm" portions  are  case-insensitive  and
       the "m" is optional.

       You  can  use either a colon or a period to separate the hours from the minutes.  That is,
       13:39 and 13.39 are equivalent.

       Remind treats timed reminders specially.  If the trigger date for a timed reminder is  the
       same as the current system date, the reminder is queued for later activation.  When Remind
       has finished processing the reminder file, it puts itself in the background, and activates
       timed reminders when the system time reached the specified time.

       If the trigger date is not the same as the system date, the reminder is not queued.

       For  example,  the  following  reminder,  triggered every working day, will emit a message
       telling you to leave at 5:00pm:

            REM Mon Tue Wed Thu Fri AT 17:00 MSG Time to leave!

       The following reminder will be triggered on Thursdays and Fridays, but will only be queued
       on Fridays:

            REM Fri ++1 AT 1:00PM MSG Lunch at 1pm Friday.

       The  tdelta  and  trepeat  have  the same form as a repeat and delta, but are specified in
       minutes.  For example, this reminder will be triggered at 12:00pm as well  as  45  minutes
       before:

            REM AT 12:00 +45 MSG Example

       The  following will be issued starting at 10:45, every half hour until 11:45, and again at
       noon.

            REM AT 12:00 +75 *30 MSG Example2

       The "+75" means that the reminder is issued starting 75  minutes  before  noon;  in  other
       words,  at  10:45.  The *30 specifies that the reminder is subsequently to be issued every
       30 minutes.  Note that the reminder is always issued at the specified time,  even  if  the
       tdelta  is  not  a  multiple  of  the trepeat.  So the above example is issued at 10:45am,
       11:15am, 11:45am, and  12:00pm.   Note  that  in  the  time  specification,  there  is  no
       distinction between the "+" and "++" forms of tdelta.

       Normally,  Remind  will issue timed reminders as it processes the reminder script, as well
       as queuing them for later.  If you  do  not  want  Remind  to  issue  the  reminders  when
       processing  the  script, but only to queue them for later, use the -a command-line option.
       If you do not want reminders to be queued for later, use the -q command-line option.

       Normally, Remind forks a background process to  handle  queued  reminders.   If  you  want
       Remind  to  remain in the foreground, use the -f command-line option.  This is useful, for
       example, in .xinitrc scripts, where you can use the command:

            remind -fa myreminders &

       This ensures that when you exit X-Windows, the Remind process is killed.

       WARNING ABOUT TIMED REMINDERS

       Note:  If you use user-defined functions or variables (described later) in the  bodies  of
       timed  reminders, then when the timed reminders are activated, the variables and functions
       have the definitions that were in effect  at  the  end  of  the  reminder  script.   These
       definitions  may not necessarily be those that were in effect at the time the reminder was
       queued.

       THE SCHED AND WARN KEYWORDS

       The SCHED keyword allows more precise control over the triggering of timed reminders,  and
       the  WARN  keyword  allows  precise  control  over  the advance triggering of all types of
       reminders.  However, discussion must be deferred until after expressions and  user-defined
       functions are explained.  See the subsection "PRECISE SCHEDULING" further on.

       TAG AND DURATION

       The  TAG keyword lets you "tag" certain reminders.  This facility is used by certain back-
       ends or systems built around Remind, such as  TkRemind.   These  back-ends  have  specific
       rules about tags; see their documentation for details.

       The  TAG  keyword is followed by a tag consisting of up to 48 characters.  You can have as
       many TAG clauses as you like in a given REM statement.

       If you supply the -y option to Remind, then any reminder that lacks a TAG  will  have  one
       synthesized.   The  synthesized  tag  consists of the characters "__syn__" followed by the
       hexadecimal representation of the MD5 sum of the REM command line.  This lets you  give  a
       more-or-less unique identifier to each distinct REM command.

       The DURATION keyword makes sense only for timed reminders; it specifies the duration of an
       event.  For example, if you have a 90-minute meeting starting at 1:00pm, you could use any
       of the following:

            REM 5 March 2021 AT 13:00 DURATION 1:30 MSG Meeting
            REM 5 March 2021 AT 13:00 DURATION 90 MSG Meeting
            REM 5 March 2021 AT 1:00pm DURATION 1:30 MSG Meeting
            REM 5 March 2021 AT 1:00pm DURATION 90 MSG Meeting

       Note that duration is specified either in hours and minutes as a time, or in minutes as an
       integer.  If you specify a duration of 00:00 or 0, then Remind behaves exactly  as  if  no
       DURATION at all had been present.

THE SUBSTITUTION FILTER

       Before being processed, the body of a REM command is passed through a substitution filter.
       The filter scans for sequences "%x" (where "x" is any letter and certain other characters)
       and  performs  substitutions  as shown below.  (All dates refer to the trigger date of the
       reminder.)

       %a     is replaced with "on weekday, day month, year"
              For example, consider the reminder:

              REM 18 Oct 1990 +4 MSG Meeting with Bob %a.

              On 16 October 1990, it would print "Meeting  with  Bob  on  Thursday,  18  October,
              1990."

              On 17 October 1990, it would print "Meeting with Bob tomorrow."

              On 18 October 1990, it would print "Meeting with Bob today."

       %b     is  replaced  with  "in  diff  day's  time" where diff is the actual number of days
              between the current date and the trigger date.  (OMITs have no effect.)
              For example, consider:

              REM 18 Oct 1990 +4 MSG Meeting with Bob %b.

              On 16 October 1990, it would print "Meeting with Bob in 2 days' time."

              On 17 October 1990, it would print "Meeting with Bob tomorrow."

              On 18 October 1990, it would print "Meeting with Bob today."

       %c     is replaced with "on weekday"
              Example: REM 18 Oct 1990 +4 MSG Meeting with Bob %c.

              On 16 October 1990, it would print "Meeting with Bob on Thursday."

              On 17 October 1990, it would print "Meeting with Bob tomorrow."

              On 18 October 1990, it would print "Meeting with Bob today."

       %d     is replaced with "day", the day of the month.

       %e     is replaced with "on dd-mm-yyyy"

       %f     is replaced with "on mm-dd-yyyy"

       %g     is replaced with "on weekday, day month"

       %h     is replaced with "on dd-mm"

       %i     is replaced with "on mm-dd"

       %j     is replaced with "on weekday, month day-th, year"  This form appends the characters
              "st", "nd", "rd" or "th" to the day of the month, as appropriate.

       %k     is replaced with "on weekday, month day-th"

       %l     is replaced with "on yyyy-mm-dd"

       %m     is replaced with "month", the name of the month.

       %n     is replaced with the number (1 to 12) of the month.

       %o     is  replaced  with " (today)" if and only if the current system date is the same as
              the date being used by Remind as the current date.  Recall that you can  specify  a
              date  for  Remind  to  use on the command line.  This substitution is not generally
              useful in a REM command, but is useful in  a  BANNER  command.   (See  "The  BANNER
              Command.")

       %p     is  replaced  with "s" if the diff between the current date and the trigger date is
              not 1.  You can use this to construct reminders like:
              REM 1 Jan +4 MSG %x day%p to go before New Year!

       %q     is replaced with "'s" if the diff between the trigger date and the current date  is
              1.  Otherwise, it is replaced with "s'"  This can be used as follows:
              REM 1 Jan +4 MSG New Year in %x day%q time!

       %r     is  replaced  with  the  day  of the month (01 to 31) padded with a leading zero if
              needed to pad to two digits.

       %s     is replaced with "st", "nd", "rd" or "th" depending on the day of the month.

       %t     is replaced with the number of the month (01 to 12) padded to  two  digits  with  a
              leading zero.

       %u     is  replaced  with  "on  weekday, day-th month, year"  This is similar to %a except
              that "st", "nd", "rd" or "th" is added to the day as appropriate.

       %v     is replaced with "on weekday, day-th month"

       %w     is replaced with "weekday", the name of the day of the week.

       %x     is replaced with the diff between the current date and the trigger date.  The  diff
              is  defined  as  the  actual  number of days between these two dates; OMITs are not
              counted.  (Strict date subtraction is performed.)

       %y     is replaced with "year", the year of the trigger date.

       %z     is replaced with "yy", the last two digits of the year.

       %_     (percent-underscore) is replaced with a newline.   You  can  use  this  to  achieve
              multi-line reminders.

       %1     is  replaced with "now", "m minutes from now", "m minutes ago", "h hours from now",
              "h hours ago", "h hours and m minutes from now" or "h hours and m minutes ago",  as
              appropriate  for  a  timed  reminder.   Note that unless you specify the -a option,
              timed reminders will be triggered like normal reminders, and thus a timed  reminder
              that  occurred  earlier  in the day may be triggered.  This causes the need for the
              "...ago" forms.

       %2     is replaced with "at hh:mmam" or "..pm" depending on the AT time of the reminder.

       %3     is replaced with "at hh:mm" in 24-hour format.

       %4     is replaced with "mm" where mm is the number of minutes between "now" and the  time
              specified  by AT.  If the AT time is earlier than the current time, then the result
              is negative.

       %5     is replaced with "ma" where ma is the absolute value of the number produced by %4.

       %6     is replaced with "ago" or "from now", depending on the relationship between the  AT
              time and the current time.

       %7     is  replaced with the number of hours between the AT time and the current time.  It
              is always non-negative.

       %8     is replaced with the number of minutes between the AT time and  the  current  time,
              after  the hours (%7) have been subtracted out.  This is a number ranging from 0 to
              59.

       %9     is replaced with "s" if the value produced by %8 is not 1.

       %0     is replaced with "s" if the value produced by %7 is not 1.

       %!     is replaced with "is" if the current time is before the AT time, or "was" if it  is
              after.

       %@     is similar to %2 but displays the current time.

       %#     is similar to %3 but displays the current time.

       %"     (percent-doublequote   -  ")  is  removed.   This  sequence  is  not  used  by  the
              substitution filter, but is used to tell Remind which text to include in a calendar
              entry when the -c, -s or -p option is chosen.  See "CALENDAR MODE"

       Notes:

       o      Remind  normally  prints a blank line after each reminder; if the last character of
              the body is "%", the blank line will not be printed.

       o      Substitutions a, b, c, e, f, g, h, i, j, k, l,  u  and  v  all  are  replaced  with
              "today"  if  the current date equals the trigger date, or "tomorrow" if the trigger
              date is one  day  after  the  current  date.   Thus,  they  are  not  the  same  as
              substitutions built up from the simpler %w, %y, etc.  sequences.

       o      The  a,  c, e, f, g, h, i, j, k, l, u, v, 2, and 3 substitutions may be preceded by
              an asterisk (for example, %*c) which causes  the  word  "at"  or  "on"  that  would
              normally be included in the output to be omitted.

       o      Any of the substitutions dealing with time (0 through 9 and '!')  produce undefined
              results if used in a reminder that does  not  have  an  AT  keyword.   Also,  if  a
              reminder  has  a delta and may be triggered on several days, the time substitutions
              ignore the date.  Thus, the %1 substitution may report that  a  meeting  is  in  15
              minutes,  for  example,  even though it may only be in 2 days time, because a delta
              has triggered the reminder.  It is recommended that you use the time  substitutions
              only  in  timed  reminders  with  no delta that are designed to be queued for timed
              activation.

       o      Capital letters can be used in the substitution sequence, in which case  the  first
              character  of the substituted string is capitalized (if it is normally a lower-case
              letter.)

       o      All other characters following a "%" sign are simply copied.  In particular, to get
              a  "%"  sign  out,  use  "%%"  in the body.  To start the body of a reminder with a
              space, use "% ", since Remind normally scans  for  the  first  non-space  character
              after a MSG, CAL or RUN token.

THE OMIT COMMAND

       In  addition  to  being  a keyword in the REM command, OMIT is a command in its own right.
       Its syntax is:

              OMIT day month [year]

              or:

              OMIT day1 month1 year1 THROUGH day2 month2 year2

       The OMIT command is used to  "globally"  omit  certain  days  (usually  holidays).   These
       globally-omitted  days  are skipped by the "-" and "+" forms of back and delta, but not by
       the "--" and "++" forms.  Some examples:

            OMIT 1 Jan
            OMIT 7 Sep 1992

       The first example specifies a holiday that occurs on the same date each year - New  Year's
       Day.   The  second  example  specifies a holiday that changes each year - Labour Day.  For
       these types of holidays, you must create an OMIT command for each year.   (Later,  in  the
       description  of expressions and some of the more advanced features of Remind, you will see
       how to automate this for some cases.)

       As with the REM command, you can use shorthand specifiers for  dates;  the  following  are
       equivalent:

            OMIT 7 Sep 1992
            OMIT 1992-09-07

       For  convenience,  you  can  use  a delta and MSG or RUN keyword in the OMIT command.  The
       following sequences are equivalent:

            OMIT 1 Jan
            REM 1 Jan +4 MSG New year's day is %b!

            and

            OMIT 1 Jan +4 MSG New year's day is %b!

       The THROUGH keyword lets you conveniently OMIT a range of days.  The starting  and  ending
       points must be fully-specified (ie, they must include day, month and year.).  For example,
       the following sequences are equivalent:

            OMIT 3 Jan 2011
            OMIT 4 Jan 2011
            OMIT 5 Jan 2011

            and

            OMIT 3 Jan 2011 THROUGH 5 Jan 2011

       You can make a THROUGH OMIT do double-duty as a REM command:

            OMIT 6 Sep 2010 THROUGH 10 Sep 2010 MSG Vacation

       You can debug your global OMITs with the following command:

            OMIT DUMP

       The OMIT DUMP command prints the current global omits to standard output.

       THE BEFORE, AFTER AND SKIP KEYWORDS

       Normally, days that are omitted, whether by a global OMIT command or  the  local  OMIT  or
       OMITFUNC keywords in a REM statement, only affect the counting of the -back or the +delta.
       For example, suppose you have a meeting every Wednesday.   Suppose,  too,  that  you  have
       indicated 11 Nov as a holiday:

            OMIT 11 Nov +4 MSG Remembrance Day
            REM Wed +1 MSG Code meeting %b.

       The  above sequence will issue a reminder about a meeting for 11 November 1992, which is a
       Wednesday.  This is probably incorrect.  There are three options:

       BEFORE This keyword moves the reminder to before any omitted days.   Thus,  in  the  above
              example, use of BEFORE would cause the meeting reminder to be triggered on Tuesday,
              10 November 1992.

       AFTER  This keyword moves the reminder to after any omitted days.  In the  above  example,
              the meeting reminder would be triggered on Thursday, 12 November 1992.

       SKIP   This  keyword  causes  the  reminder  to be skipped completely on any omitted days.
              Thus, in the above example, the reminder would not  be  triggered  on  11  November
              1992.   However,  it  would  be  triggered  as usual on the following Wednesday, 18
              November 1992.

       The BEFORE and AFTER keywords move the trigger date of a reminder to  before  or  after  a
       block  of  omitted days, respectively.  Suppose you normally run a backup on the first day
       of the month.  However, if the first day of the month is a weekend or holiday, you run the
       backup on the first working day following the weekend or holiday.  You could use:

            REM 1 OMIT Sat Sun AFTER RUN do_backup

       Let's  examine  how  the  trigger  date is computed.  The 1 specifies the first day of the
       month.  The local OMIT keyword causes the AFTER keyword to move the reminder forward  past
       weekends.   Finally,  the AFTER keyword will keep moving the reminder forward until it has
       passed any holidays specified with global OMIT commands.

THE DO AND INCLUDE COMMANDS

       Remind allows you to include other files  in  your  reminder  script,  similar  to  the  C
       preprocessor  #include  directive.   For example, your system administrator may maintain a
       file of holidays or system-wide reminders.  You can include these in your reminder  script
       as follows:

            INCLUDE /usr/share/remind/holidays
            INCLUDE /usr/share/remind/reminders

       (The actual pathnames vary from system to system - ask your system administrator.)

       INCLUDE files can be nested up to a depth of 8.

       If  you  specify  a filename of "-" in the INCLUDE command, Remind will begin reading from
       standard input.

       If you specify a directory as the argument to INCLUDE, then Remind will process all  files
       in that directory that match the shell patterm "*.rem".  The files are processed in sorted
       order; the sort order matches that used by the shell when it expands "*.rem".

       Note that the file specified by an INCLUDE command is interpreted relative to the  current
       working  directory  of  the Remind process.  If you want to include a file relative to the
       directory containing the currently-processing file, use DO instead.  For example,  if  the
       current   file   is   /home/user/.reminders/foo.rem  and  Remind's  working  directory  is
       /home/user, then:

           # Read /home/user/.reminders/bar.rem
           DO bar.rem

           # Read /usr/share/bar.rem - absolute path
           DO /usr/share/bar.rem

           # Read /home/user/bar.rem
           INCLUDE bar.rem

           # Read /usr/share/bar.rem - absolute path
           INCLUDE /usr/share/bar.rem

       Arguably, the INCLUDE command should have worked the way DO does right from the start, but
       changing it would have broken backward-compatibility, hence the introduction of DO.

THE RUN COMMAND

       If  you include other files in your reminder script, you may not always entirely trust the
       contents of the other files.  For example, they may contain RUN-type reminders that  could
       be  used  to access your files or perform undesired actions.  The RUN command can restrict
       this:  If you include the command RUN OFF in your top-level reminder script, any  reminder
       or  expression  that would normally execute a system command is disabled.  RUN ON will re-
       enable the execution of system commands.  Note that the RUN ON command can only be used in
       your  top-level  reminder  script;  it  will not work in any files accessed by the INCLUDE
       command.  This is to protect you from someone placing a RUN  ON  command  in  an  included
       file.  However, the RUN OFF command can be used at top level or in an included file.

       If  you  run  Remind  with  the -r command-line option, RUN-type reminders and the shell()
       function will be disabled,  regardless  of  any  RUN  commands  in  the  reminder  script.
       However, any command supplied with the -k option will still be executed.

       One  use  of  the  RUN command is to provide a secure interface between Remind and the Elm
       mail system.  The Elm system can automatically scan incoming mail for reminder or calendar
       entries,  and  place  them in your calendar file.  To use this feature, you should set the
       calendar filename option under Elm to be something like "~/.reminders.in", not  your  main
       reminder file!  This is so that any RUN ON commands mailed to you can never be activated.

       Then,  you  can  use  the Elm scan message for calendar entries command to place reminders
       prefaced by "->" into .reminders.in.  In your main .reminders file, include the  following
       lines:

            RUN OFF   # Disable RUN
            INCLUDE .reminders.in
            RUN ON    # Re-enable RUN

       In  addition, Remind contains a few other security features.  It will not read a file that
       is group- or world-writable.  It will not run set-uid.  If it reads a file you don't  own,
       it will disable RUN and the shell() function.  And if it is run as root, it will only read
       files owned by root.

       Note that if Remind reads standard input, it does not attempt to check  the  ownership  of
       standard  input,  even  if  it  is  coming from a file, and hence does not disable RUN and
       shell() in this situation.

THE INCLUDECMD COMMAND

       Remind allows you to execute a shell command and evaluate the output of that command as if
       it  were an included file.  For example, you could have scripts that extract reminders out
       of a database and print them on stdout as REM commands.  Here is an example:

            INCLUDECMD extract_reminders_for dfs

       We assume that the command "extract_reminders_for" extracts reminders  out  of  a  central
       database for the named user.  Another use-case of INCLUDECMD is if you have your reminders
       stored in a file in some non-Remind format; you can write a command that  transforms  them
       to  Remind  format  and  then Remind can "include" the file with an appropriate INCLUDECMD
       command.

       Note that if RUN is disabled, then INCLUDECMD  will  fail  with  the  error  message  "RUN
       disabled"

       INCLUDECMD  passes  the rest of the line to popen(3), meaning that the command is executed
       by the shell.  As such, shell metacharacters  may  need  escaping  or  arguments  quoting,
       depending on what you're trying to do.  Remind itself does not perform any modification of
       the command line (apart from the normal [expr] expression-pasting mechanism).

       If the command passed to INCLUDECMD begins with  an  exclamation  mark  "!",  then  Remind
       disables RUN for the output of the command.  If you are running a command whose output you
       don't quite trust, you should prefix it with "!" so that any RUN commands it emits fail.

       An INCLUDECMD command counts towards the INCLUDE nesting depth.  For any given Remind run,
       a given INCLUDECMD command is only executed once and the results are cached.  For example,
       if you generate a calendar, each unique INCLUDECMD command is run just once, not once  for
       each  day  of the produced calendar.  "Uniqueness" is determined by looking at the command
       that will be passed to the shell, so if (for example)  your  INCLUDECMD  uses  expression-
       pasting  that  results  in differences depending on the value of today(), then each unique
       version of the command will be executed once.

THE BANNER COMMAND

       When Remind first issues a reminder, it prints a message like this:

            Reminders for Friday, 30th October, 1992 (today):

       (The banner is not printed if any of the calendar-producing options is used, or if the  -k
       option is used.)

       The  BANNER command lets you change the format.  It should appear before any REM commands.
       The format is:

              BANNER format

       The format is similar to the body of a REM command.  It is passed through the substitution
       filter,  with an implicit trigger of the current system date.  Thus, the default banner is
       equivalent to:

            BANNER Reminders for %w, %d%s %m, %y%o:

       You can disable the banner completely with BANNER %.  Or you can create a custom banner:

            BANNER Hi - here are your reminders for %y-%t-%r:

CONTROLLING THE OMIT CONTEXT

       Sometimes, it is necessary to temporarily change the global OMITs that are in force for  a
       few reminders.  Three commands allow you to do this:

       PUSH-OMIT-CONTEXT
              This command saves the current global OMITs on an internal stack.

       CLEAR-OMIT-CONTEXT
              This command clears all of the global OMITs, starting you off with a "clean slate."

       POP-OMIT-CONTEXT
              This  command  restores  the  global OMITs that were saved by the most recent PUSH-
              OMIT-CONTEXT.

       For example, suppose you have a block of reminders that require a clear OMIT context,  and
       that  they also introduce unwanted global OMITs that could interfere with later reminders.
       You could use the following fragment:

            PUSH-OMIT-CONTEXT   # Save the current context
            CLEAR-OMIT-CONTEXT  # Clean the slate
            # Block of reminders goes here
            POP-OMIT-CONTEXT    # Restore the saved omit context

EXPRESSIONS

       In certain contexts, to be described later, Remind will accept expressions for evaluation.
       Remind expressions resemble C expressions, but operate on different types of objects.

       DATA TYPES

       Remind expressions operate on five types of objects:

       INT    The  INT data type consists of the integers representable in one machine word.  The
              INT data type corresponds to the C "int" type.

       STRING The STRING data type consists of strings of characters.  It is somewhat  comparable
              to a C character array, but more closely resembles the string type in BASIC.

       TIME   The  TIME data type consists of times of the day.  The TIME data type is internally
              stored as an integer representing the number of minutes since midnight.

       DATE   The DATE data type consists of dates (later than 1 January 1990.)  Internally, DATE
              objects are stored as the number of days since 1 January 1990.

       DATETIME
              The  DATETIME data type consists of a date and time together.  Internally, DATETIME
              objects are stored as the number of minutes since midnight, 1  January  1990.   You
              can think of a DATETIME object as being the combination of DATE and TIME parts.

       CONSTANTS

       The following examples illustrate constants in Remind expressions:

       INT constants
              12, 36, -10, 0, 1209

       STRING constants
              "Hello there", "This is a test", "\n\gosd\w", ""

              Note  that  the empty string is represented by "", and that backslashes in a string
              are not interpreted specially, as in they are in C.

       TIME constants
              12:33, 0:01, 14:15, 16:42, 12.16, 13.00, 1.11, 4:30PM, 12:20am

              Note that TIME constants may be written in 24-hour  format  or  in  common  "AM/PM"
              format.  If you use "AM/PM" format, then the hour can range from 1 to 12.  Either a
              period or colon can be used to separate  the  minutes  from  the  hours.   However,
              Remind  will  consistently  output times in 24-hour format using only one separator
              character.  (The output separator character is chosen at compile-time.)

       DATE constants
              DATE constants are expressed as 'yyyy/mm/dd' or 'yyyy-mm-dd', and the single quotes
              must  be  supplied.  This distinguishes date constants from division or subtraction
              of integers.  Examples:

              '1993/02/22', '1992-12-25', '1999/01/01'

              Note that DATE values are printed without the quotes.  Although either '-'  or  '/'
              is  accepted as a date separator on input, when dates are printed, only one will be
              used.  The choice of whether to use '-' or '/' is made at compile-time.  Note  also
              that versions of Remind prior to 03.00.01 did not support date constants.  In those
              versions, you must create dates using the date() function.  Also, versions prior to
              03.00.02 did not support the '-' date separator.

       DATETIME constants
              DATETIME  constants  are expressed similarly to DATE constants with the addition of
              an "@HH:MM" part, optionally followed by "am" or "pm".  For example:

              '2008-04-05@23:11', '1999/02/03@14:06', '2001-04-07@08:30', '2020-01-01@3:20pm'

              DATETIME values are  printed  without  the  quotes.   Notes  about  date  and  time
              separator characters for DATE and TIME constants apply also to DATETIME constants.

       OPERATORS

       Remind  has  the  following  operators.  Operators on the same line have equal precedence,
       while operators on lower lines have lower precedence than  those  on  higher  lines.   The
       operators approximately correspond to C operators.

            !  -     (unary logical negation and arithmetic negation)
            *  /  %
            +  -
            <  <=  >  >=
            ==  !=
            &&
            ||

       DESCRIPTION OF OPERATORS

       !      Logical  negation.   Can  be  applied  to an INT type.  If the operand is non-zero,
              returns zero.  Otherwise, returns 1.

       -      Unary minus.  Can be applied to an INT.  Returns the negative of the operand.

       *      Multiplication.  Returns the product of two INTs.

       /      Integer division.  Returns the quotient of two INTs, discarding the remainder.

       %      Modulus.  Returns the remainder upon dividing one INT by another.

       +      Has several uses.  These are:

              INT + INT - returns the sum of two INTs.

              INT + TIME or TIME + INT - returns a TIME obtained by adding  INT  minutes  to  the
              original TIME.  The result will always range from 00:00 through 23:59.

              TIME  +  TIME  treats  the second TIME parameter as a duration, converting it to an
              integer number of minutes past midnight, and then performs addition as with TIME  +
              INT.

              INT  +  DATE  or  DATE  +  INT  - returns a DATE obtained by adding INT days to the
              original DATE.

              INT + DATETIME or DATETIME + INT -  returns  a  DATETIME  obtained  by  adding  INT
              minutes to the original DATETIME.

              DATETIME  +  TIME  or  TIME  +  DATETIME  treats  the TIME parameter as a duration,
              converting it to an integer number of minutes  past  midnight,  and  then  performs
              addition as with DATETIME + INT.

              STRING  +  STRING  - returns a STRING that is the concatenation of the two original
              STRINGs.

              STRING + anything or anything + STRING - converts  the  non-STRING  argument  to  a
              STRING, and then performs concatenation.  See the coerce() function.

       -      Has several uses.  These are:

              INT - INT - returns the difference of two INTs.

              DATE - DATE - returns (as an INT) the difference in days between two DATEs.

              TIME - TIME - returns (as an INT) the difference in minutes between two TIMEs.

              DATETIME  -  DATETIME  -  returns (as an INT) the difference in minutes between two
              DATETIMEs.

              DATE - INT - returns a DATE that is INT days earlier than the original DATE.

              TIME - INT - returns a TIME that is INT minutes earlier than the original TIME.

              DATETIME - INT - returns a DATETIME that is INT minutes earlier than  the  original
              DATETIME.

              DATETIME  -  TIME  -  coerces  the  TIME to an INT and then performs subtraction as
              above.

       <, <=, >, and >=
              These are the comparison operators.  They can take operands of any type,  but  both
              operands  must  be  of  the  same  type.   The comparison operators return 1 if the
              comparison is true, or 0 if it is false.   Note  that  string  comparison  is  done
              following  the  lexical  ordering  of characters on your system, and that upper and
              lower case are distinct for these operators.

       ==, != == tests for equality, returning 1 if its operands are equal, and  0  if  they  are
              not.  != tests for inequality.

              If  the  operands  are not of the same type, == returns 0 and != returns 1.  Again,
              string comparisons are case-sensitive.

       &&     This is the logical AND operator.  Both of its operands must be of  type  INT.   It
              returns 1 if both operands are non-zero, and 0 otherwise.

       ||     This  is  the  logical  OR operator.  Both of its operands must be of type INT.  It
              returns 1 if either operand is non-zero, and 0 otherwise.

       NOTES

       If the result of an addition, subtraction or multiplication operation would not fit in a C
       "int"  type,  Remind  issues a "Number too high" error.  Unlike C, integer operations will
       not simply give the wrong answer in case of overflow.

       Operators of equal precedence are always  evaluated  from  left  to  right,  except  where
       parentheses  dictate  otherwise.   This is important, because the enhanced "+" operator is
       not necessarily associative.  For example:

            1 + 2 + "string" + 3 + 4  yields "3string34"
            1 + (2 + "string") + (3 + 4)  yields "12string7"
            12:59 + 1 + "test"  yields "13:00test"
            12:59 + (1 + "test")  yields "12:591test"

       The logical operators are not so-called short-circuit operators, as they are in  C.   Both
       operands are always evaluated.  Thus, an expression such as:

            (f!=0) && (100/f <= 3)

       will cause an error if f is zero.

       VARIABLES

       Remind allows you to assign values to variables.  The SET command is used as follows:

       SET var expr

       Var  is  the  name  of a variable.  It must start with a letter or underscore, and consist
       only of letters, digits and underscores.  Only the first 64 characters of a variable  name
       are  significant.   Variable names are not case sensitive; thus, "Afoo" and "afOo" are the
       same variable.  Examples:

            SET a 10 + (9*8)
            SET b "This is a test"
            SET mydir getenv("HOME")
            SET time 12:15
            SET date today()

       Note that variables themselves have no type.  They take on the type of whatever you  store
       in them.

       Variables set with SET or on the command-line with -ivar=expr have global scope.

       To delete a variable, use the UNSET command:

       UNSET var [var...]

       For example, to delete all the variables declared above, use:

            UNSET a b mydir time date

       SYSTEM VARIABLES

       In  addition to the regular user variables, Remind has several "system variables" that are
       used to query or control the operating state of Remind.  System  variables  are  available
       starting from version 03.00.07 of Remind.

       All  system  variables begin with a dollar sign '$'.  They can be used in SET commands and
       expressions just as regular variables can.  All system variables always hold values  of  a
       specified  type.   In  addition,  some system variables cannot be modified, and you cannot
       create new system variables.  System variables can be initialized on the command line with
       the  -i  option,  but  you  may need to quote them to avoid having the shell interpret the
       dollar sign.  System variable names are not case-sensitive.

       The following system variables are defined.  Those marked "read-only"  cannot  be  changed
       with  the  SET  command.   All  system variables hold values of type INT, unless otherwise
       specified.

       $CalcUTC
              If 1 (the default), then Remind uses C library functions to calculate the number of
              minutes  between  local  and Universal Time Coordinated.  This affects astronomical
              calculations (sunrise() for example.)  If 0, then you must  supply  the  number  of
              minutes  between  local  and  Universal Time Coordinated in the $MinsFromUTC system
              variable.

       $CalMode (read-only)
              If non-zero, then the -c option was supplied on the command line.

       $Daemon (read-only)
              If the daemon mode -z was invoked, contains the number of minutes between  wakeups.
              If not running in daemon mode, contains 0.

       $DateSep
              This  variable  can  be  set  only  to  "/" or "-".  It holds the character used to
              separate portions of a date when Remind prints a DATE or DATETIME value.

       $DefaultColor
              This variable can be set to a string that has the  form  of  three  space-separated
              numbers.   Each  number must be an integer from 0 to 255, or all three numbers must
              be -1.  The default value of $DefaultColor is "-1 -1 -1", which suppresses  default
              coloring  of MSG-type reminders.  If you set $DefaultColor to any other value, then
              all MSG-, MSF- and CAL-type reminders are effectively converted into SPECIAL  COLOR
              reminders whose color value is specified by $DefaultColor.

              Unlike  other system variables, the value of $DefaultColor is not preserved between
              calendar iterations; rather, it is reset to  "-1  -1  -1"  at  the  start  of  each
              iteration.

       $DefaultPrio
              The  default priority assigned to reminders without a PRIORITY clause.  You can set
              this as required to adjust the priorities of blocks of reminders without having  to
              type priorities for individual reminders.  At startup, $DefaultPrio is set to 5000;
              it can range from 0 to 9999.

       $DefaultTDelta
              The default time delta used if no +N is given in an AT clause.  This is normally 0,
              but  can  be  set  with  the  -tt  option  or  explicitly  set  in your script.  If
              $DefaultDelta is non-zero, you can use an explicit delta of +0 in an AT  clause  to
              countermand the default delta.

       $DontFork (read-only)
              If non-zero, then the -c option was supplied on the command line.

       $DontTrigAts (read-only)
              The number of times that the -a option was supplied on the command line.

       $DontQueue (read-only)
              If non-zero, then the -q option was supplied on the command line.

       $EndSent (STRING type)
              Contains  a  list  of  characters that end a sentence.  The MSF keyword inserts two
              spaces after these characters.   Initially,  $EndSent  is  set  to  ".!?"  (period,
              exclamation mark, and question mark.)

       $EndSentIg (STRING type)
              Contains  a  list  of characters that should be ignored when MSF decides whether or
              not to place two spaces after a sentence.  Initially, is  set  to  "'>)]}"+CHAR(34)
              (single-quote,  greater-than,  right  parenthesis,  right bracket, right brace, and
              double-quote.)

              For example, the default values work as follows:

                   MSF He said, "Huh! (Two spaces will follow this.)"  Yup.

              because the final parenthesis and quote are ignored (for the purposes  of  spacing)
              when they follow a period.

       $FirstIndent
              The number of spaces by which to indent the first line of a MSF-type reminder.  The
              default is 0.

       $FoldYear
              The standard Unix library functions may have difficulty dealing  with  dates  later
              than  2037.   If  this  variable is set to 1, then the UTC calculations "fold back"
              years later than 2037 before using the Unix library  functions.   For  example,  to
              find  out  whether or not daylight saving time is in effect in June, 2077, the year
              is "folded back" to 2010, because both years begin on a Monday, and both  are  non-
              leapyears.   The  rules  for daylight saving time are thus presumed to be identical
              for both years, and the Unix library functions can handle 2010.  By  default,  this
              variable is 0.  Set it to 1 if the sun or UTC functions misbehave for years greater
              than 2037.

       $FormWidth
              The maximum width of each line of text  for  formatting  MSF-type  reminders.   The
              default  is the width of the terminal in columns, minus 8, but clamped at a minimum
              of 20 and a maximum of 500.  If standard output is not a terminal, then the default
              is  72.If  an  MSF-type  reminder contains a word too long to fit in this width, it
              will not be truncated - the width limit will be ignored.

       $HushMode (read-only)
              If non-zero, then the -h option was supplied on the command line.

       $IgnoreOnce (read-only)
              If non-zero, then the -o option was  supplied  on  the  command  line,  or  a  date
              different  from  today's true date was supplied.  If non-zero, then ONCE directives
              will be ignored.

       $InfDelta (read-only)
              If non-zero, then the -t option was supplied on the command line.

       $IntMax (read-only)
              The largest representable INT.  On a machine  with  32-bit  signed  integers  using
              twos-complement representation, this will be 2147483647.

       $IntMin (read-only)
              The  smallest  representable  INT.   On a machine with 32-bit signed integers using
              twos-complement representation, this will be -2147483648.

       $Latitude (STRING type)
              The latitude of your location, expressed as  a  string  that  is  a  floating-point
              number.   Because  Remind  does  not  have a native floating-point type, we need to
              express it as a string.  $Latitude can range from "-90.0" to "90.0", with  positive
              numbers  representing points north of the equator and negative numbers representing
              south.

       $Longitude (STRING type)
              The longitude of your location, expressed as a  string  that  is  a  floating-point
              number.   Because  Remind  does  not  have a native floating-point type, we need to
              express it as a string.  $Longitude  can  range  from  "-180.0"  to  "180.0",  with
              positive  numbers  representing  points east of the Greenwich Meridian and negative
              numbers representing west.

              For example, the coordinates of  the  Statue  of  Liberty  in  New  York  City  are
              approximately set by:
                      SET $Latitude   "40.68933"
                      SET $Longitude "-74.04454"

       $LatDeg, $LatMin, $LatSec (DEPRECATED)
              These specify the latitude of your location.  $LatDeg can range from -90 to 90, and
              the others from -59 to 59.  Northern latitudes  are  positive;  southern  ones  are
              negative.   For southern latitudes, all three components should be negative.  These
              three variables are deprecated; you should use $Latitude instead.

       $Location (STRING type)
              This is a string specifying the name of your location.  It is usually the  name  of
              your  town  or  city.  It can be set to whatever you like, but good style indicates
              that it should be kept consistent with the latitude and longitude system variables.

       $LongDeg, $LongMin, $LongSec (DEPRECATED)
              These specify the longitude of your location.  $LongDeg can range from -180 to 180.
              Western  longitudes  are  positive; eastern ones are negative.  Note that all three
              components should have the same sign: All positive for western longitudes  and  all
              negative  for  eastern  longitudes.  Note that for historical reasons, the sign for
              longitude is different from the usual convention!  If you  find  the  longitude  of
              your location from a search engine, you will most likely need to invert the sign to
              have it work correctly with Remind.  These  three  variables  are  deprecated;  you
              should  use  $Longitude  instead.   Note  also  that  $Longitude  uses the standard
              convention of negative for western longitudes and positive for eastern ones.

              The latitude and longitude information is required for the functions sunrise()  and
              sunset().   Default  values can be compiled into Remind, or you can SET the correct
              values at the start of your reminder scripts.

              Note that setting  any  of  $LongDec,  $LongMin  and  $LongSec  updates  $Longitude
              correspondingly,  and  setting  $Longitude updates $LongDeg, $LongMin and $LongSec.
              Similar rules apply to $Latitude, $LatDeg, $LatMin and $LatSec.

       $MaxSatIter
              The maximum number of iterations for the SATISFY clause (described later.)  Must be
              at least 10.

       $MaxStringLen
              A limit on the longest string that Remind will allow you to create.  The default is
              65535.  If you set $MaxStringLen to 0 or to -1,  then  remind  will  allow  you  to
              create arbitrarily-long strings, at least until it runs out of memory.

       $MinsFromUTC
              The  number  of  minutes  between  Universal  Time  Coordinated and local time.  If
              $CalcUTC is non-zero, this is calculated upon startup of  Remind.   Otherwise,  you
              must  set  it  explicitly.   If  $CalcUTC is zero, then $MinsFromUTC is used in the
              astronomical calculations.  You must adjust it for daylight saving  time  yourself.
              Also,  if you want to initialize $MinsFromUTC using the -i command-line option, you
              must also set $CalcUTC to 0 with the -i option.

       $NextMode (read-only)
              If non-zero, then the -n option was supplied on the command line.

       $NumQueued (read-only)
              Contains the number of reminders queued so far for background timed triggering.

       $NumTrig (read-only)
              Contains the number of reminders triggered for the current date.  One use for  this
              variable  is  as  follows:   Suppose  you  wish to shade in the box of a PostScript
              calendar whenever a holiday is triggered.  You could save the value of $NumTrig  in
              a  regular  variable prior to executing a block of holiday reminders.  If the value
              of $NumTrig after the holiday block is greater than the saved value, then at  least
              one holiday was triggered, and you can execute the command to shade in the calendar
              box.  (See the section "Calendar Mode".)

              Note that $NumTrig is affected only by REM commands; triggers in IFTRIG commands do
              not affect it.

       $PrefixLineNo (read-only)
              If non-zero, then the -l option was supplied on the command line.

       $PSCal (read-only)
              If non-zero, then the -p option was supplied on the command line.

       $RunOff (read-only)
              If non-zero, the RUN directives are disabled.

       $SimpleCal (read-only)
              Set  to  a  non-zero  value  if  either  of  the  -p or -s command-line options was
              supplied.

       $SortByDate (read-only)
              Set to 0 if no -g option is used, 1 if sorting by date in ascending order, or 2  if
              sorting by date in descending order.

       $SortByPrio (read-only)
              Set to 0 if no -g option is used, 1 if sorting by priority in ascending order, or 2
              if sorting by priority in descending order.

       $SortByTime (read-only)
              Set to 0 if no -g option is used, 1 if sorting by time in ascending order, or 2  if
              sorting by time in descending order.

       $SubsIndent
              The  number of spaces by which all lines (except the first) of an MSF-type reminder
              should be indented.  The default is 0.

       $T (read-only, DATE type)
              Exactly equivalent to trigdate().  (See BUILT-IN FUNCTIONS.)

       $Td (read-only)
              Equivalent to day(trigdate()).

       $Tm (read-only)
              Equivalent to monnum(trigdate()).

       $Tw (read-only)
              Equivalent to wkdaynum(trigdate()).

       $Ty (read-only)
              Equivalent to year(trigdate()).

       $TimeSep
              This variable can be set only to ":" or  ".".   It  holds  the  character  used  to
              separate portions of a time when Remind prints a TIME or DATETIME value.

       $UntimedFirst (read-only)
              Set  to  1  if  the -g option is used with a fourth sort character of "d"; set to 0
              otherwise.

       $U (read-only, DATE type)
              Exactly equivalent to today().  (See BUILT-IN FUNCTIONS.)

       $Ud (read-only)
              Equivalent to day(today()).

       $Um (read-only)
              Equivalent to monnum(today()).

       $Uw (read-only)
              Equivalent to wkdaynum(today()).

       $Uy (read-only)
              Equivalent to year(today()).

       Note:  If any of the calendar modes are in effect, then the values of $Daemon,  $DontFork,
       $DontTrigAts,  $DontQueue,  $HushMode,  $IgnoreOnce,  $InfDelta,  and  $NextMode  are  not
       meaningful.

       BUILT-IN FUNCTIONS

       Remind has a plethora of built-in functions.  The syntax for a function call is  the  same
       as  in C - the function name, followed a comma-separated list of arguments in parentheses.
       Function names are not case-sensitive.  If a function  takes  no  arguments,  it  must  be
       followed  by "()" in the function call.  Otherwise, Remind will interpret it as a variable
       name, and probably not work correctly.

       In the descriptions below, short forms  are  used  to  denote  acceptable  types  for  the
       arguments.   The  characters "i", "s", "d", "t" and "q" denote INT, STRING, DATE, TIME and
       DATETIME arguments, respectively.  If an  argument  can  be  one  of  several  types,  the
       characters are concatenated.  For example, "di_arg" denotes an argument that can be a DATE
       or an INT.  "x_arg" denotes an argument that can be of any type.  The type of the argument
       is followed by an underscore and an identifier naming the argument.

       The built-in functions are:

       abs(i_num)
              Returns the absolute value of num.

       access(s_file, si_mode)
              Tests the access permissions for the file file.  Mode can be a string, containing a
              mix of the characters  "rwx"  for  read,  write  and  execute  permission  testing.
              Alternatively, mode can be a number as described in the UNIX access(2) system call.
              The function returns 0 if the file can be accessed with the specified mode, and  -1
              otherwise.

       adawn([dq_date])
              Returns the time of "astronomical dawn" on the specified date.  If date is omitted,
              defaults to today().  If a datetime object is supplied, only the date component  is
              used.

       adusk([dq_date])
              Returns  the  time  of  "astronomical  twilight" on the specified date.  If date is
              omitted, defaults to today().

       ampm(tq_time [,s_am [,s_pm]])
              Returns a STRING that is the result of converting time (which is either a TIME or a
              DATETIME  object)  to  "AM/PM"  format.   The  optional arguments am and pm are the
              strings to append in the AM and PM case, respectively; they  default  to  "AM"  and
              "PM".   The function obeys the system variables $DateSep, $TimeSep and $DateTimeSep
              when formatting its output.  For example:

                      ampm(0:22)                 returns "12:22AM"
                      ampm(17:45, "am", "pm")    returns "5:45pm"
                      ampm('2020-03-14@21:34')   returns "2020-03-14@9:34PM"

       args(s_fname)
              Returns the number of arguments expected by the user-defined function fname, or  -1
              if  no  such  user-defined  function exists.  Note that this function examines only
              user-defined functions, not built-in functions.   Its  main  use  is  to  determine
              whether or not a particular user-defined function has been defined previously.  The
              args() function is available only in versions of Remind from 03.00.04 and up.

       asc(s_string)
              Returns an INT that is the ASCII code of the  first  character  in  string.   As  a
              special case, asc("") returns 0.

       baseyr()
              Returns  the  "base year" that was compiled into Remind (normally 1990.)  All dates
              are stored internally as the number of days since 1 January of baseyr().

       char(i_i1 [,i_i2...])
              This function can take any number of INT arguments.  It returns a STRING consisting
              of  the characters specified by the arguments.  Note that none of the arguments can
              be 0, unless there is only one argument.  As a special case, char(0) returns "".

              Note that because Remind does not support escaping of characters  in  strings,  the
              only way to get a double-quote in a string is to use char(34).

       choose(i_index, x_arg1 [,x_arg2...])
              Choose must take at least two arguments, the first of which is an INT.  If index is
              n, then the nth subsequent argument is returned.  If index is  less  than  1,  then
              arg1  is  returned.   If  index is greater than the number of subsequent arguments,
              then the last argument is returned.  Examples:

                 choose(0, "foo", 1:13, 1000) returns "foo"
                 choose(1, "foo", 1:13, 1000) returns "foo"
                 choose(2, "foo", 1:13, 1000) returns 1:13
                 choose(3, "foo", 1:13, 1000) returns 1000
                 choose(4, "foo", 1:13, 1000) returns 1000
              Note that all arguments to choose() are always evaluated.

       coerce(s_type, x_arg)
              This function converts arg to the specified type, if such conversion  is  possible.
              Type  must  be  one  of  "INT",  "STRING",  "DATE",  "TIME"  or  "DATETIME"  (case-
              insensitive).  The conversion rules are as follows:

              If arg is already of the type specified, it is returned unchanged.

              If type is "STRING", then arg is converted to a string consisting  of  its  printed
              representation.

              If type is "DATE", then an INT arg is converted by interpreting it as the number of
              days since 1 January baseyr().  A STRING arg is converted by attempting to read  it
              as  if  it  were a printed date.  A DATETIME is converted to a date by dropping the
              time component.  A TIME arg cannot be converted to a date.

              If type is "TIME", then an INT arg is converted by interpreting it as the number of
              minutes  since  midnight.  A STRING arg is converted by attempting to read it as if
              it were a printed time.  A DATETIME is converted to a time  by  dropping  the  date
              component.  A DATE arg cannot be converted to a time.

              If  type  is  "DATETIME",  then  an  INT arg is converted by interpreting it as the
              number of minutes since midnight, 1 January baseyr().  A  STRING  is  converted  by
              attempting  to  read  it  as  if it were a printed datetime.  Other types cannot be
              converted to a datetime.

              If type is "INT", then DATE, TIME and DATETIME arguments are  converted  using  the
              reverse  of procedures described above.  A STRING arg is converted by parsing it as
              an integer.

       current()
              Returns the current date and time as a DATETIME object.  This  may  be  the  actual
              date and time, or may be the date and time supplied on the command line.

       date(i_y, i_m, i_d)
              The  date()  function returns a DATE object with the year, month and day components
              specified by y, m and d.

       datepart(dq_datetime)
              Returns a DATE object representing the date portion of datetime.

       datetime(args)
              The datetime() function can take anywhere from two to five  arguments.   It  always
              returns a DATETIME generated from its arguments.

              If you supply two arguments, the first must be a DATE and the second a TIME.

              If  you  supply  three arguments, the first must be a DATE and the second and third
              must be INTs.  The second and third arguments are interpreted as hours and  minutes
              and converted to a TIME.

              If  you  supply  four  arguments,  the first three must be INTs, interpreted as the
              year, month and day.  The fourth argument must be a TIME.

              Finally, if you supply five arguments, they must all be INTs and are interpreted as
              year, month, day, hour and minute.

       dawn([dq_date])
              Returns  the  time  of  "civil  dawn"  on  the specified date.  If date is omitted,
              defaults to today().  If a datetime object is supplied, only the date component  is
              used.

       day(dq_date)
              This  function  takes a DATE or DATETIME as an argument, and returns an INT that is
              the day-of-month component of date.

       daysinmon(i_m, i_y)
              Returns the number of days in month m (1-12) of the year y.

       defined(s_var)
              Returns 1 if the variable named by var is defined, or 0 if it is not.
              Note that defined() takes a STRING argument;  thus,  to  check  if  variable  X  is
              defined, use:

                        defined("X")

              and not:

                        defined(X)

              The  second  example  will attempt to evaluate X, and will return an error if it is
              undefined or not of type STRING.

       dosubst(s_str [,d_date [,t_time]]) or dosubst(s_str [,q_datetime])
              Returns a STRING that is the result of passing str through the substitution  filter
              described  earlier.   The  parameters  date  and  time  (or datetime) establish the
              effective trigger date and time used by the substitution filter.  If date and  time
              are omitted, they default to today() and now().

              Note  that  if  str does not end with "%", a newline character will be added to the
              end of the result.  Also, calling dosubst() with a date that is in the past  (i.e.,
              if date < today()) will produce undefined results.

              Dosubst() is only available starting from version 03.00.04 of Remind.

       dusk([dq_date])
              Returns  the  time  of "civil twilight" on the specified date.  If date is omitted,
              defaults to today().

       easterdate(dqi_arg)
              If arg is an INT, then returns the date of Easter Sunday for  the  specified  year.
              If arg is a DATE or DATETIME, then returns the date of the next Easter Sunday on or
              after arg.  (The time component of a datetime is ignored.)

       evaltrig(s_trigger [,dq_start])
              Evaluates trigger as if it were a REM or IFTRIG trigger specification  and  returns
              the  trigger date as a DATE (or as a DATETIME if there is an AT clause.)  Returns a
              negative INT if no trigger could be computed.

              Normally, evaltrig finds a trigger date on or after today.  If you supply the start
              argument, then it scans starting from there.

              For example, the expression:

                evaltrig("Mon 1", '2008-10-07')

              returns  '2008-11-03', since that is the first date on or after 7 October 2008 that
              satisfies "Mon 1".

              If you want to see how many days it is from the first Monday in  October,  2008  to
              the first Monday in November, 2008, use:

                evaltrig("Mon 1", '2008-11-01') - evaltrig("Mon 1", '2008-10-01')

              and  the  answer  is  28.   The trigger argument to evaltrig can have all the usual
              trigger clauses (OMIT, AT, SKIP,  etc.)  but  cannot  have  a  SATISFY,  MSG,  etc.
              reminder-type clause.

       filedate(s_filename)
              Returns  the  modification  date  of  filename.  If filename does not exist, or its
              modification date is before the year  baseyr(),  then  1  January  of  baseyr()  is
              returned.

       filedatetime(s_filename)
              Returns the modification date and time of filename.  If filename does not exist, or
              its modification date is before the year baseyr(),  then  midnight,  1  January  of
              baseyr() is returned.

       filedir()
              Returns  the directory that contains the current file being processed.  It may be a
              relative or absolute pathname, but is guaranteed  to  be  correct  for  use  in  an
              INCLUDE command as follows:

                 INCLUDE [filedir()]/stuff

              This  includes  the  file  "stuff"  in the same directory as the current file being
              processed.  Note that this workaround is no longer necessary because DO stuff  will
              achieve the same goal.

       filename()
              Returns  (as  a  STRING)  the  name  of the current file being processed by Remind.
              Inside included files, returns the name of the included file.

       getenv(s_envvar)
              Similar to the getenv(2) system call.  Returns a string representing the  value  of
              the  specified environment variable.  Returns "" if the environment variable is not
              defined.  Note  that  the  names  of  environment  variables  are  generally  case-
              sensitive; thus, getenv("HOME") is not the same as getenv("home").

       hebdate(i_day, s_hebmon [,idq_yrstart [,i_jahr [,i_aflag]]])
              Support for Hebrew dates - see the section "THE HEBREW CALENDAR"

       hebday(dq_date)
              Support for Hebrew dates - see the section "THE HEBREW CALENDAR"

       hebmon(dq_date)
              Support for Hebrew dates - see the section "THE HEBREW CALENDAR"

       hebyear(dq_date)
              Support for Hebrew dates - see the section "THE HEBREW CALENDAR"

       hour(tq_time)
              Returns the hour component of time.

       iif(si_test1, x_arg1, [si_test2, x_arg2,...], x_default)
              If  test1 is not zero or the null string, returns arg1.  Otherwise, if test2 is not
              zero or the null string, returns arg2, and so on.  If all of the test arguments are
              false,  returns  default.   Note  that  all  arguments  are always evaluated.  This
              function accepts an odd number of arguments - note that prior to  version  03.00.05
              of  Remind,  it  accepted  3  arguments  only.   The 3-argument version of iif() is
              compatible with previous versions of Remind.

       index(s_search, s_target [,i_start)
              Returns an INT that is the location of target in  the  string  search.   The  first
              character of a string is numbered 1.  If target does not exist in search, then 0 is
              returned.

              The optional parameter start specifies the position in search  at  which  to  start
              looking for target.

       isany(arg1 [,arg2, ..., argN]);
              Returns  1  if  the first argument arg1 is equal to any of the subsequent arguments
              arg2 through argN; returns 0 otherwise.  Also returns 0 if  called  with  only  one
              argument.

              As an example, the following two expressions are equivalent:

                      (a == b) || (a == c) || (a == d) || (a == e)

                      isany(a, b, c, d, e)

       isdst([d_date [,t_time]]) or isdst(q_datetime)
              Returns  a  positive  number  if daylight saving time is in effect on the specified
              date and time.  Date defaults to today() and time defaults to midnight.

              Note that this function is only as reliable as the C  run-time  library  functions.
              It is available starting with version 03.00.07 of Remind.

       isleap(idq_arg)
              Returns  1  if  arg  is  a  leap year, and 0 otherwise.  Arg can be an INT, DATE or
              DATETIME object.  If a DATE or DATETIME is supplied, then  the  year  component  is
              used in the test.

       isomitted(dq_date)
              Returns  1  if  date  is omitted, given the current global OMIT context.  Returns 0
              otherwise.  (If a datetime is supplied, only the date part is used.)  Note that any
              local OMIT or OMITFUNC clauses are not taken into account by this function.

       language()
              Returns  a STRING naming the language supported by Remind.  (See "SUPPORT FOR OTHER
              LANGUAGES") By default, Remind is compiled to support  English  messages,  so  this
              function  returns  "English".   For  other languages, this function will return the
              English name of the language (e.g. "German") Note that language() is not  available
              in versions of Remind prior to 03.00.02.

       lower(s_string)
              Returns a STRING with all upper-case characters in string converted to lower-case.

       max(x_arg1 [,x_arg2...)
              Can take any number of arguments, and returns the maximum.  The arguments can be of
              any type, but must all be of the same type.   They  are  compared  as  with  the  >
              operator.

       min(x_arg1 [,x_arg2...)
              Can take any number of arguments, and returns the minimum.  The arguments can be of
              any type, but must all be of the same type.   They  are  compared  as  with  the  <
              operator.

       minsfromutc([d_date [,t_time]]) or minsfromutc(q_datetime)
              Returns  the  number  of  minutes from Universal Time Coordinated (formerly GMT) to
              local time on the specified date and time.   Date  defaults  to  today()  and  time
              defaults  to  midnight.   If  local  time  is  before  UTC, the result is negative.
              Otherwise, the result is positive.

              Note that this function is only as reliable as the C  run-time  library  functions.
              It is available starting with version 03.00.07 of Remind.

       minute(tq_time)
              Returns the minute component of time.

       mon(dqi_arg)
              If arg is of DATE or DATETIME type, returns a string that names the month component
              of the date.  If arg is an INT from 1 to 12, returns a string that names the month.

       monnum(dq_date)
              Returns an INT from 1 to 12, representing the month component of date.

       moondate(i_phase [,d_date [,t_time]]) or moondate(i_phase, q_datetime)
              This function returns the date of the first occurrence of the phase  phase  of  the
              moon on or after date and time.  Phase can range from 0 to 3, with 0 signifying new
              moon, 1 first quarter, 2 full moon, and 3 third quarter.  If date  is  omitted,  it
              defaults to today().  If time is omitted, it defaults to midnight.

              For example, the following returns the date of the next full moon:

                        SET fullmoon moondate(2)

       moontime(i_phase [,d_date [,t_time]]) or moontime(i_phase, q_datetime)
              This  function  returns  the time of the first occurrence of the phase phase of the
              moon on or after date and time.  Phase can range from 0 to 3, with 0 signifying new
              moon,  1  first  quarter, 2 full moon, and 3 third quarter.  If date is omitted, it
              defaults to today().  If time is omitted, it defaults to midnight.   Moontime()  is
              intended  to be used in conjunction with moondate().  The moondate() and moontime()
              functions are accurate to within a couple of minutes of the times in "Old  Farmer's
              Almanac" for Ottawa, Ontario.

              For example, the following returns the date and time of the next full moon:

                        MSG Next full moon at [moontime(2)] on [moondate(2)]

       moondatetime(i_phase [,d_date [,t_time]]) or moondatetime(i_phase, q_datetime)
              This function is similar to moondate and moontime, but returns a DATETIME result.

       moonphase([d_date [,t_time]]) or moonphase(q_datetime)
              This  function  returns  the  phase  of the moon on date and time, which default to
              today() and midnight, respectively.  The returned value is an  integer  from  0  to
              359, representing the phase of the moon in degrees.  0 is a new moon, 180 is a full
              moon, 90 is first-quarter, etc.

       ndawn([dq_date])
              Returns the time of "nautical dawn" on the specified date.   If  date  is  omitted,
              defaults  to today().  If a datetime object is supplied, only the date component is
              used.

       ndusk([dq_date])
              Returns the time of "nautical twilight" on the specified date.  If date is omitted,
              defaults to today().

       nonomitted(dq_start, dq_end [,s_wkday...])
              This  function  returns  the  number of non-omitted days between start and end.  If
              start is non-omitted, then it is counted.  end is never counted.

              Note that end must be greater than or equal to start or an error is  reported.   In
              addition to using the global OMIT context, you can supply additional arguments that
              are names of weekdays to be omitted.  However, in a REM command, any local OMITFUNC
              clause is not taken into account by this function.

              For example, the following line sets a to 11 (assuming no global OMITs):

                   set a nonomitted('2007-08-01', '2007-08-16', "Sat", "Sun")

              because Thursday, 16 August 2007 is the 11th working day (not counting Saturday and
              Sunday) after Wednesday, 1 August 2007.

              nonomitted has various uses.  For example, many schools run on a six-day cycle  and
              the day number is not incremented on holidays.  Suppose the school year starts with
              Day 1 on 4 September 2007.  The following reminder will  label  day  numbers  in  a
              calendar:

                 IF today() >= '2007-09-04'
                     set daynum nonomitted('2007-09-04', today(), "Sat", "Sun")
                     REM OMIT SAT SUN SKIP CAL Day [(daynum % 6) + 1]
                 ENDIF

              Obviously,  the  answer you get from nonomitted depends on the global OMIT context.
              If you use moveable OMITs, you may get inconsistent results.

              Here is a more complex use for  nonomitted.   My  garbage  collection  follows  two
              interleaved  14-day  cycles:  One Friday, garbage and paper recycling ("Black Box")
              are collected.  The next Friday, garbage and plastic  recycling  ("Blue  Box")  are
              collected.   If  any of Monday-Friday is a holiday, collection is delayed until the
              Saturday.  Here's a way to encode these rules:

                 fset _garbhol(x) wkdaynum(x) == 5 && nonomitted(x-4, x+1) < 5
                 REM 12 November 1999 *14 AFTER OMITFUNC _garbhol MSG Black Box
                 REM 19 November 1999 *14 AFTER OMITFUNC _garbhol MSG Blue Box

              Here's how it works:  The _garbhol(x) user-defined function returns 1 if  and  only
              if  (1)  x  is a Friday and (2) there is at least one OMITted day from the previous
              Monday up to and including the Friday.

              The first REM statement sets up the 14-day  black-box  cycle.   The  AFTER  keyword
              makes  it  move  collection  to the Saturday if _garbhol returns 1.  The second REM
              statement sets up the 14-day blue-box cycle with a similar adjustment made by AFTER
              in conjunction with _garbhol.

       now()  Returns the current system time, as a TIME type.  This may be the actual time, or a
              time supplied on the command line.

       ord(i_num)
              Returns a string that is the ordinal  number  num.   For  example,  ord(2)  returns
              "2nd", and ord(213) returns "213th".

       ostype()
              Returns "UNIX".  Remind used to run on OS/2 and MS-DOS, but does not any longer.

       plural(i_num [,s_str1 [,s_str2]])
              Can  take from one to three arguments.  If one argument is supplied, returns "s" if
              num is not 1, and "" if num is 1.

              If two arguments are supplied, returns str1 + "s" if  num  is  not  1.   Otherwise,
              returns str1.

              If three arguments are supplied, returns str1 if num is 1, and str2 otherwise.

       psmoon(i_phase [,i_size [,s_note [,i_notesize]]])
              [DEPRECATED]  Returns  a STRING consisting of PostScript code to draw a moon in the
              upper-left hand corner of the calendar box.  Phase specifies the phase of the moon,
              and  is  0  (new  moon), 1 (first quarter), 2 (full moon) or 3 (third quarter).  If
              size is specified, it controls the radius of the moon  in  PostScript  units  (1/72
              inch.)   If  it is not specified or is negative, the size of the day-number font is
              used.

              For example, the  following  four  lines  place  moon  symbols  on  the  PostScript
              calendar:

                        REM [moondate(0)] PS [psmoon(0)]
                        REM [moondate(1)] PS [psmoon(1)]
                        REM [moondate(2)] PS [psmoon(2)]
                        REM [moondate(3)] PS [psmoon(3)]

              If  note  is specified, the text is used to annotate the moon display.  The font is
              the same font used for calendar entries.  If notesize is given,  it  specifies  the
              font  size to use for the annotation, in PostScript units (1/72 inch.)  If notesize
              is not given, it defaults to the size used for calendar entries.  (If you  annotate
              the  display,  be  careful not to overwrite the day number -- Remind does not check
              for this.)  For example, if you want the time of each new moon displayed, you could
              use this in your reminder script:

                   REM [moondate(0)] PS [psmoon(0, -1, moontime(0)+"")]

              Note how the time is coerced to a string by concatenating the null string.

       psshade(i_gray) or psshade(i_red, i_green, i_blue)
              [DEPRECATED]  Returns  a  STRING  that  consists  of PostScript commands to shade a
              calendar box.  Num can range from 0 (completely black) to 100  (completely  white.)
              If  three arguments are given, they specify red, green and blue intensity from 0 to
              100.  Here's an example of how to use this:

                        REM Sat Sun PS [psshade(95)]

              The above command emits PostScript code to lightly shade the boxes for Saturday and
              Sunday in a PostScript calendar.

              Note  that  psmoon  and  psshade are deprecated; instead you should use the SPECIAL
              SHADE and SPECIAL MOON reminders as described in "Out-of-Band Reminders."

       realcurrent()
              Returns (as a DATETIME) the true date and time of day as provided by the  operating
              system.   This is in contrast to current(), which may return a time supplied on the
              command line.

       realnow()
              Returns the true time of day as provided by  the  operating  system.   This  is  in
              contrast to now(), which may return a time supplied on the command line.

       realtoday()
              Returns  the  date  as  provided  by  the operating system.  This is in contrast to
              Remind's concept of "today", which may be changed if  it  is  running  in  calendar
              mode, or if a date has been supplied on the command line.

       sgn(i_num)
              Returns -1 if num is negative, 1 if num is positive, and 0 if num is zero.

       shell(s_cmd [,i_maxlen])
              Executes  cmd  as  a system command, and returns the first 511 characters of output
              resulting from cmd.  Any whitespace character in  the  output  is  converted  to  a
              space.   Note  that if RUN OFF has been executed, or the -r command-line option has
              been used, shell() will result in an error, and cmd will not be executed.

              If maxlen is specified, then shell() returns the first maxlen characters of  output
              (rather  than the first 511).  If maxlen is specified as a negative number, then it
              defaults to the value of the system variable $MaxStringLen.

       shellescape(s_str)
              Returns str with all shell metacharacters such as " ",  "*",  etc  escaped  with  a
              backslash.  For example:

               SET a shellescape("a b*? c&d$e")

              will set a to:

               "a\ b\*\?\ c\&d\$e"

       slide(d_start, i_amt [,s_wkday...])
              This  function  is  the  inverse  of  nonomitted.   It  adds amt days (which can be
              negative) to start, not counting omitted days.  The optional  wkday  arguments  are
              additional weekday names to omit.

              Consider this example:

                   OMIT 14 May 2009
                   SET a slide('2009-05-13', 5, "Sat", "Sun")

              In  this  case, a is set to 2009-05-21.  That's because we slide forward by 5 days,
              not including Thursday, May 14 or Saturday and Sunday, May 16 and 17.  You  can  go
              backwards, too, so:

                   OMIT 14 May 2009
                   SET a slide('2009-05-21', -5, "Sat", "Sun")

              takes a back to 2009-05-13.

       strlen(s_str)
              Returns  the  length  of str.  If the length of str is too large to represent as an
              integers, emits a "Number too high" error.

       substr(s_str, i_start [,i_end])
              Returns a STRING consisting of all characters in str from start up to and including
              end.   Characters are numbered from 1.  If end is not supplied, then it defaults to
              the length of str.

       sunrise([dq_date])
              Returns a TIME indicating the time  of  sunrise  on  the  specified  date  (default
              today().)  In high latitudes, there may be no sunrise on a particular day, in which
              case sunrise() returns the INT 0 if the sun never sets, or 1440 if it never rises.

       sunset([dq_date])
              Returns a TIME indicating the  time  of  sunset  on  the  specified  date  (default
              today().)   In high latitudes, there may be no sunset on a particular day, in which
              case sunset() returns the INT 0 if the sun never rises, or 1440 if it never sets.

              The functions sunrise() and sunset() are based on  an  algorithm  in  "Almanac  for
              Computers for the year 1978" by L. E. Doggett, Nautical Almanac Office, USNO.  They
              require the latitude and longitude to  be  specified  by  setting  the  appropriate
              system  variables.  (See "System Variables".)  The sun functions should be accurate
              to within about 4 minutes for latitudes lower than 60 degrees.  The  functions  are
              available starting from version 03.00.07 of Remind.

       time(i_hr, i_min)
              Creates a TIME with the hour and minute components specified by hr and min.

       timepart(tq_datetime)
              Returns a TIME object representing the time portion of datetime.

       today()
              Returns  Remind's notion of "today."  This may be the actual system date, or a date
              supplied on the command line, or the date of the  calendar  entry  currently  being
              computed.

       trigdate()
              Returns  the calculated trigger date of the last REM or IFTRIG command.  If used in
              the body of a REM command, returns that command's trigger date.  If the most recent
              REM command did not yield a computable trigger date, returns the integer 0.

       trigdatetime()
              Similar  to  trigdate(),  but returns a DATETIME if the most recent triggerable REM
              command had an AT clause.  If there was no  AT  clause,  returns  a  DATE.   If  no
              trigger  could be computed, returns the integer 0.  See "MULTI-DAY EVENTS" for more
              information.

       trigeventstart()
              Returns a DATETIME representing the  start  of  the  most  recent  triggerable  REM
              command  that  had an AT clause.  For events without a DURATION or that do not span
              multiple days, returns the same as trigdatetime().  If the REM command did not have
              an  AT  clause,  returns  the  integer  -1 (and differs from trigdatetime() in this
              respect.)  See "MULTI-DAY EVENTS" for more information.

       trigeventduration()
              Returns a TIME representing the duration of the most recent triggerable REM command
              that  had  an  AT and a DURATION clause.  If the event does not span multiple days,
              returns the same thing as trigduration().  If the  REM  command  lacked  an  AT  or
              DURATION clause, returns -1.  See "MULTI-DAY EVENTS" for more information.

       trigback()
              Returns  the  "back"  amount of the last REM or IFTRIG command.  Returns a positive
              integer N if the "back" is of the form -N, or a negative integer if it  is  of  the
              form --N.  If there is no "back", then returns 0.

       trigdelta()
              Returns  the  "delta" amount of the last REM or IFTRIG command.  Returns a positive
              integer N if the "delta" is of the form +N, or a negative integer if it is  of  the
              form ++N.  If there is no "delta", then returns 0.

       trigtimedelta()
              Similar  to  trigdelta(),  but  returns  the delta used in the AT clause of a timed
              reminder.

       trigrep()
              Returns the "repeat" amount of the last REM or IFTRIG command.  Returns a  positive
              integer N if the "repeat" is of the form *N.  If there is no "repeat", then returns
              0.

       trigtimerep()
              Similar to trigrep(), but returns the repeat used in  the  AT  clause  of  a  timed
              reminder.

       trigduration()
              Returns  (as  a TIME type) the DURATION parameter of a timed reminder.  If there is
              no DURATION parameter, returns the integer -1.  See  "MULTI-DAY  EVENTS"  for  more
              information.

       trigpriority()
              Returns the PRIORITY of the last REM or IFTRIG command.

       triguntil()
              Returns (as a DATE type) the UNTIL parameter of the last REM or IFTRIG command.  If
              there was no UNTIL parameter, returns the  integer  -1.   If  there  is  a  THROUGH
              parameter,  that  will  be  returned  by  triguntil() since "THROUGH yyyy-mm-dd" is
              simply syntactic sugar for "*1 UNTIL yyyy-mm-dd".

       trigscanfrom()
              Returns (as a DATE type) the SCANFROM parameter of the last REM or IFTRIG  command.
              If  there  was  no  SCANFROM parameter, returns the integer -1.  Note that FROM and
              SCANFROM interact; a reminder that has a "FROM yyyy-mm-dd" parameter will act as if
              it has a SCANFROM parameter whose value is the maximum of "yyyy-mm-dd" and today.

       trigfrom()
              Returns  (as a DATE type) the FROM parameter of the last REM or IFTRIG command.  If
              there was no FROM parameter, returns the integer -1.

       trigger(d_date [,t_time [,i_utcflag]]) or trigger(q_datetime [,i_utcflag])
              Returns a string suitable for use in a REM command or a SCANFROM or  UNTIL  clause,
              allowing  you to calculate trigger dates in advance.  Note that in earlier versions
              of Remind, trigger was required to convert a date into something  the  REM  command
              could  consume.   However,  in  this version of Remind, you can omit it.  Note that
              trigger() always returns its result in English, even for  non-English  versions  of
              Remind.   Normally,  the  date  and  time  are the local date and time; however, if
              utcflag is non-zero, the date and time  are  interpreted  as  UTC  times,  and  are
              converted to local time.  Examples:

                   trigger('1993/04/01')

              returns "1 April 1993",

                   trigger('1994/08/09', 12:33)

              returns "9 August 1994 AT 12:33", as does:

                   trigger('1994/08/09@12:33').

              Finally:

                   trigger('1994/12/01', 03:00, 1)

              returns  "30  November  1994  AT  22:00" for EST, which is 5 hours behind UTC.  The
              value for your time zone may differ.

       trigtime()
              Returns the time of the last REM command with an AT clause.  If the  last  REM  did
              not  have  an  AT clause, returns the integer 0.  If a REM command has an AT clause
              with a DURATION, then you can compute the end time as trigtime() + trigduration().

       trigvalid()
              Returns 1 if the value returned by trigdate() is valid  for  the  most  recent  REM
              command,  or  0 otherwise.  Sometimes REM commands cannot calculate a trigger date.
              For example, the following REM command can never be triggered:

                 REM Mon OMIT Mon SKIP MSG Impossible!

       typeof(x_arg)
              Returns "STRING", "INT", "DATE", "TIME" or "DATETIME", depending  on  the  type  of
              arg.

       tzconvert(q_datetime, s_srczone [,s_dstzone])
              Converts  datetime  from  the  time zone named by srczone to the time zone named by
              dstzone.  If dstzone is omitted, the default system time zone is used.  The  return
              value  is a DATETIME.  Time zone names are system-dependent; consult your operating
              system for legal values.  Here is an example:

           tzconvert('2007-07-08@01:14', "Canada/Eastern", "Canada/Pacific")

                 returns

           2007-07-07@22:14

       upper(s_string)
              Returns a STRING with all lower-case characters in string converted to upper-case.

       value(s_varname [,x_default])
              Returns the value of the specified variable.  For example,  value("X"+"Y")  returns
              the  value  of  variable  XY,  if  it  is  defined.  If XY is not defined, an error
              results.

              However, if you supply a second argument, it is returned  if  the  varname  is  not
              defined.  The expression value("XY", 0) will return 0 if XY is not defined, and the
              value of XY if it is defined.

       version()
              Returns a string specifying the version of Remind.  For version  03.00.04,  returns
              "03.00.04".   It  is  guaranteed  that  as new versions of Remind are released, the
              value returned by version() will strictly increase,  according  to  the  rules  for
              string ordering.

       weekno([dq_date, [i_wkstart, [i_daystart]]])
              Returns the week number of the year.  If no arguments are supplied, returns the ISO
              8601 week number for today().  If one argument date is supplied, then  returns  the
              ISO  8601  week  number for that date.  If two arguments are supplied, then wkstart
              must range from 0 to 6, and represents the first day of  the  week  (with  0  being
              Sunday  and 6 being Saturday.).  If wkstart is not supplied, then it defaults to 1.
              If the third argument daystart is supplied, then it specifies when Week  1  starts.
              If  daystart is less than or equal to 7, then Week 1 starts on the first wkstart on
              or after January daystart.  Otherwise, Week 1 starts on the  first  wkstart  on  or
              after  December  daystart.   If omitted, daystart defaults to 29 (following the ISO
              8601 definition.)

       wkday(dqi_arg)
              If arg is a DATE or DATETIME, returns a string representing the day of the week  of
              the  date.   If  arg  is  an  INT  from  0  to 6, returns the corresponding weekday
              ("Sunday" to "Saturday").

       wkdaynum(dq_date)
              Returns a number from 0 to 6 representing the day-of-week of  the  specified  date.
              (0 represents Sunday, and 6 represents Saturday.)

       year(dq_date)
              Returns a INT that is the year component of date.

MULTI-DAY EVENTS

       If  you  specify  a start time with AT and a duration with DURATION, you can create events
       that span multiple days.  Consider these two REM statements:

           REM 1991-02-13 AT 16:00 DURATION 72:00 MSG 72-hour event
           REM 1991-02-13 THROUGH 1991-02-16 AT 16:00 MSG Four events

       The first statement creates a single event that starts on 13 February 1991  at  16:00  and
       runs through 16 February 1991 at 16:00

       The  second  statements creates four separate events that start at 16:00 on 13, 14, 15 and
       16 February 1991 and have indefinite duration.

       Remind handles multi-day events specially.  These are the rules:

       On the first day of a multi-day event, trigdatetime() will return the  starting  date  and
       time of the event, and trigduration() will return the original DURATION.

       On  each  subsequent  day of a multi-day event, trigdatetime() will return midnight on the
       day in question, and trigduration() will return the  remaining  duration.   Consider  this
       example:

           #!/bin/sh
           remind - 12 feb 1991 '*6' <<'EOF'
           BANNER %
           REM 1991-02-13 AT 16:00 DURATION 72:00 SATISFY 1
           set a trigdatetime()
           set b trigduration()
           set c trigeventstart()
           set d trigeventduration()
           MSG now=[today()] dt=[a] dur=[b] estart=[c] edur=[d]%
           EOF

       The output is:

       now=1991-02-12 dt=1991-02-13@16:00 dur=72:00 estart=1991-02-13@16:00 edur=72:00
       now=1991-02-13 dt=1991-02-13@16:00 dur=72:00 estart=1991-02-13@16:00 edur=72:00
       now=1991-02-14 dt=1991-02-14@00:00 dur=64:00 estart=1991-02-13@16:00 edur=72:00
       now=1991-02-15 dt=1991-02-15@00:00 dur=40:00 estart=1991-02-13@16:00 edur=72:00
       now=1991-02-16 dt=1991-02-16@00:00 dur=16:00 estart=1991-02-13@16:00 edur=72:00
       now=1991-02-17 dt=1991-02-13@16:00 dur=72:00 estart=-1 edur=-1

       As  you  see,  the  trigdatetime()  and trigduration() functions return the start time and
       duration of the remaining  portion  of  a  multi-day  event,  whereas  trigeventstart  and
       trigeventduration  always  return  the original start and duration of the multi-day event.
       Note also that the return value for expired reminders  is  not  reliable;  the  fact  that
       trigeventstart and trigeventduration return -1 in that case is an implementation artifact.

       SELF-OVERLAPPING EVENTS

       A  multi-day event has the possibility of "overlapping itself".  When this happens, Remind
       prefers the later event (only one copy of an event is ever triggered for  a  given  date.)
       Consider this example:

          #!/bin/sh
          remind - '*5' 10 Feb 1991 <<'EOF'

          BANNER %
          REM MON at 0:00 DURATION 192:0 MSG [today()] [trigeventstart()] [trigduration()]%

          EOF

       The output is:

          1991-02-10 1991-02-04@00:00 48:00
          1991-02-11 1991-02-11@00:00 192:00
          1991-02-12 1991-02-11@00:00 168:00
          1991-02-13 1991-02-11@00:00 144:00
          1991-02-14 1991-02-11@00:00 120:00

       Although  the  event  from  1991-02-04  still  has  24 hours left on 1991-02-11, the fresh
       occurrence on 1991-02-11 takes precedences and is the one that is triggered.

       I do not recommend constructing self-overlapping multi-day events.

EXPRESSION PASTING

       An extremely powerful feature of Remind is its macro capability, or "expression pasting."

       In almost any situation where Remind is not expecting an expression, you  can  "paste"  an
       expression in.  To do this, surround the expression with square brackets.  For example:

            REM [mydate] MSG foo

       This  evaluates  the  expression  "mydate", where "mydate" is presumably some pre-computed
       variable, and then "pastes" the result into the command-line for the parser to process.

       A formal description of this is:  When Remind  encounters  a  "pasted-in"  expression,  it
       evaluates  the  expression,  and  coerces the result to a STRING.  It then substitutes the
       string  for  the  pasted-in  expression,  and  continues  parsing.   Note,  however,  that
       expressions are evaluated only once, not recursively.  Thus, writing:

            ["[a+b]"]

       causes  Remind  to  read  the  token  "[a+b]".   It does not interpret this as a pasted-in
       expression.  In fact, the only way to get a literal left-bracket into a reminder is to use
       ["["].

       You can use expression pasting almost anywhere.  However, there are a few exceptions:

       o      If Remind is expecting an expression, as in the SET command, or the IF command, you
              should not include square brackets.  For example, use:

                 SET a 4+5
       and not:
                 SET a [4+5]

       o      You cannot use expression pasting for the first token on a line.  For example,  the
              following will not work:

                 ["SET"] a 1

              This  restriction  is  because  Remind  must be able to unambiguously determine the
              first token of a line for the flow-control commands (to be discussed later.)

              In fact, if Remind cannot determine the first token on a line, it assumes  that  it
              is  a  REM  command.   If  expression-pasting  is  used, Remind assumes it is a REM
              command.  Thus, the following three commands are equivalent:

                        REM 12 Nov 1993 AT 13:05 MSG BOO!
                        12 Nov 1993 AT 13:05 MSG BOO!
                        [12] ["Nov " + 1993] AT [12:05+60] MSG BOO!

       o      You cannot use expression-pasting to determine the type (MSG, CAL, etc.) of  a  REM
              command.   You  can  paste expressions before and after the MSG, etc. keywords, but
              cannot do something like this:

                 REM ["12 Nov 1993 AT 13:05 " + "MSG" + " BOO!"]

       COMMON PITFALLS IN EXPRESSION PASTING

       Remember, when pasting  in  expressions,  that  extra  spaces  are  not  inserted.   Thus,
       something like:

            REM[expr]MSG[expr]

       will probably fail.

       If  you  use  an  expression  to  calculate  a  delta or back, ensure that the result is a
       positive number.  Something like:

            REM +[mydelta] Nov 12 1993 MSG foo

       will fail if mydelta happens to be negative.

FLOW CONTROL COMMANDS

       Remind has commands that control the  flow  of  a  reminder  script.   Normally,  reminder
       scripts are processed sequentially.  However, IF and related commands allow you to process
       files conditionally, and skip sections that you don't want interpreted.

       THE IF COMMAND

       The IF command has the following form:

            IF expr
                 t-command
                 t-command...
            ELSE
                 f-command
                 f-command...
            ENDIF

       Note that the commands are shown indented for clarity.  Also,  the  ELSE  portion  can  be
       omitted.  IF commands can be nested up to a small limit, probably around 8 or 16 levels of
       nesting, depending on your system.

       If the expr evaluates to a non-zero INT, or a non-null STRING,  then  the  IF  portion  is
       considered true, and the t-commands are executed.  If expr evaluates to zero or null, then
       the f-commands (if the ELSE portion is present) are executed.  If expr is not of type  INT
       or STRING, then it is an error.

       Examples:

            IF defined("want_hols")
                 INCLUDE /usr/share/remind/holidays
            ENDIF

            IF today() > '1992/2/10'
                 set missed_ap "You missed it!"
            ELSE
                 set missed_ap "Still have time..."
            ENDIF

       THE IFTRIG COMMAND

       The  IFTRIG  command is similar to an IF command, except that it computes a trigger (as in
       the REM command), and evaluates to true if a  corresponding  REM  command  would  trigger.
       Examples:

            IFTRIG 1 Nov
                 ; Executed on 1 Nov
            ELSE
                 ; Executed except on 1 Nov
            ENDIF

            IFTRIG 1 -1 OMIT Sat Sun +4
                 ; Executed on last working day of month,
                 ; and the 4 working days preceding it
            ELSE
                 ; Executed except on above days
            ENDIF

       Note  that  the  IFTRIG  command  computes a trigger date, which can be retrieved with the
       trigdate() function.  You can use all of the normal trigger  components,  such  as  UNTIL,
       delta,  etc. in the IFTRIG command.  However, you cannot use a type specifier such as CAL,
       MSG or SATISFY; attempting to do so yields a parse error.

USER-DEFINED FUNCTIONS

       In addition to the built-in functions, Remind allows you to  define  your  own  functions.
       The FSET command does this for you:

       FSET fname(args) expr

       Fname  is the name of the function, and follows the convention for naming variables.  Args
       is a comma-separated list of arguments, and expr is an expression.  Args can be empty,  in
       which case you define a function taking no parameters.  Here are some examples:

            FSET double(x) 2*x
            FSET yeardiff(date1, date2) year(date1) - year(date2)
            FSET since(x) ord(year(trigdate())-x)

       The last function is useful in birthday reminders.  For example:

            REM 1 Nov +12 MSG Dean's [since(1984)] birthday is %b.

       Dean was born in 1984.  The above example, on 1 November 1992, would print:

            Dean's 8th birthday is today.

       Notes:

       o      If you access a variable in expr that is not in the list of arguments, the "global"
              value (if any) is used.

       o      Function and parameter names are significant only to 12 characters.

       o      The value() function always accesses the "global" value of a variable, even  if  it
              has the same name as an argument.  For example:

                        fset func(x) value("x")
                        set x 1
                        set y func(5)

              The above sequence sets y to 1, which is the global value of x.

       o      User-defined  functions  may  call  other  functions,  including other user-defined
              functions.  However, recursive calls are not allowed.

       o      User-defined functions are not syntax-checked when they are defined; parsing occurs
              only when they are called.

       o      If  a user-defined function has the same name as a built-in function, it is ignored
              and the built-in function is used.  To prevent conflicts with  future  versions  of
              Remind  (which  may define more built-in functions), you may wish to name all user-
              defined functions beginning with an underscore.

PRECISE SCHEDULING

       The WARN keyword allows precise control over advance warning in  a  more  flexible  manner
       than  the  delta mechanism.  It should be followed by the name of a user-defined function,
       warn_function.

       If a warn_function is supplied, then it must  take  one  argument  of  type  INT.   Remind
       ignores  any  delta, and instead calls warn_function successively with the arguments 1, 2,
       3, ...

       Warn_function's return value n is interpreted as follows:

       o      If n is positive, then the reminder is triggered exactly n days before its  trigger
              date.

       o      If n is negative, then it is triggered n days before its trigger date, not counting
              OMITted days.

       As an example, suppose you wish to be warned of American Independence Day 5, 3, and 1 days
       in advance.  You could use this:

            FSET _wfun(x) choose(x, 5, 3, 1, 0)
            REM 4 July WARN _wfun MSG American Independence Day is %b.

       NOTES

       1      If  an  error  occurs  during  the  evaluation  of warn_function, then Remind stops
              calling it and simply issues the reminder on its trigger date.

       2      If the absolute-values of the return values of warn_function are not  monotonically
              decreasing, Remind stops calling it and issues the reminder on its trigger date.

       3      Warn_function should (as a matter of good style) return 0 as the final value in its
              sequence of return values.  However, a reminder will always  be  triggered  on  its
              trigger date, regardless of what warn_function does.

       Similarly  to  WARN, the SCHED keyword allows precise control over the scheduling of timed
       reminders.  It should be followed by the name of a user-defined function, sched_function.

       If a scheduling function is supplied, then it must take one argument of type INT.   Rather
       than  using the AT time, time delta, and time repeat, Remind calls the scheduling function
       to determine when to trigger the reminder.  The first time the  reminder  is  queued,  the
       scheduling function is called with an argument of 1.  Each time the reminder is triggered,
       it is re-scheduled by calling the scheduling function again.  On each call,  the  argument
       is incremented by one.

       The return value of the scheduling function must be an INT or a TIME.  If the return value
       is a TIME, then the reminder is re-queued to trigger at that time.  If it  is  a  positive
       integer  n,  then the reminder is re-queued to trigger at the previous trigger time plus n
       minutes.  Finally, if it is a negative integer or zero, then the reminder is re-queued  to
       trigger  n minutes before the AT time.  Note that there must be an AT clause for the SCHED
       clause to do anything.

       Here's an example:

            FSET _sfun(x) choose(x, -60, 30, 15, 10, 3, 1, 1, 1, 1, 0)
            REM AT 13:00 SCHED _sfun MSG foo

       The reminder would first be triggered at 13:00-60 minutes, or at 12:00.  It would next  be
       triggered 30 minutes later, at 12:30.  Then, it would be triggered at 12:45, 12:55, 12:58,
       12:59, 13:00, 13:01 and 13:02.

       NOTES

       1      If an error occurs during the evaluation of  sched_func,  then  Remind  reverts  to
              using  the  AT  time  and  the  delta and repeat values, and never calls sched_func
              again.

       2      If processing sched_func yields a time earlier than the current system time, it  is
              repeatedly  called with increasing argument until it yields a value greater than or
              equal to the current time.  However, if the sequence of  values  calculated  during
              the  repetition  is  not  strictly  increasing,  then Remind reverts to the default
              behaviour and never calls sched_func again.

       3      It is quite possible using sched_func to keep triggering a reminder even after  the
              AT-time.   However,  it is not possible to reschedule a reminder past midnight - no
              crossing of date boundaries is allowed.  Also, it is quite possible to not  trigger
              a  reminder  on  the  AT time when you use a scheduling function.  However, if your
              scheduling function is terminated (for reasons 1 and 2) before the AT time  of  the
              reminder,  it  will  be  triggered  at the AT time, because normal processing takes
              over.

       4      Your scheduling functions should (as a matter of good style) return 0 when no  more
              scheduling is required.  See the example.

       5      All scheduling functions are evaluated after the entire Remind script has been read
              in.  So whatever function definitions are in effect at the end of  the  script  are
              used.

THE SATISFY CLAUSE

       The form of REM that uses SATISFY is as follows:

       REM trigger SATISFY expr

       The  way  this works is as follows:  Remind first calculates a trigger date, in the normal
       fashion.  Next, it sets trigdate() to the calculated  trigger  date.   It  then  evaluates
       expr.   If  the result is not the null string or zero, processing ends.  Otherwise, Remind
       computes the next trigger date, and re-tests expr.  This iteration  continues  until  expr
       evaluates  to  non-zero  or  non-null,  or until the iteration limit specified with the -x
       command-line option is reached.

       If expr is not satisfied, then trigvalid() is set  to  0  and  the  error  message  "Can't
       compute trigger" is issued.  Otherwise, trigvalid() is set to 1.

       This is really useful only if expr involves a call to the trigdate() or related functions;
       otherwise, expr will not change as Remind iterates.

       An example of the usefulness of SATISFY:  Suppose you wish to be warned  of  every  Friday
       the 13th.  Your first attempt may be:

            # WRONG!
            REM Fri 13 +2 MSG Friday the 13th is %b.

       But  this  won't work.  This reminder triggers on the first Friday on or after the 13th of
       each month.  The way to do it is with a more complicated sequence:

            REM 13 SATISFY wkdaynum(trigdate()) == 5
            IF trigvalid()
                 REM [trigdate()] +2 MSG \
                 Friday the 13th is %b.
            ENDIF

       You can write the REM statement a little more concisely:

            REM 13 SATISFY $Tw == 5

       Let's see how this works.  The SATISFY clause iterates through all the 13ths of successive
       months, until a trigger date is found whose day-of-week is Friday (== 5).  If a valid date
       was found, we use the calculated trigger date to set up the next reminder.

       We could also have written:

            REM Fri SATISFY day(trigdate()) == 13

       but this would result in more iterations, since "Fridays" occur more often than "13ths  of
       the month."

       Here  is  another  example:  Suppose  you  want to be reminded of something on the 15th of
       January, April, July, and October.  You could make four separate reminders, or  you  could
       use:

               REM 15 SATISFY [isany($Tm, 1, 4, 7, 10)] MSG 15th Reminder!

       This  technique of using one REM command to calculate a trigger date to be used by another
       command is quite powerful.  For example, suppose you wanted to OMIT Labour day,  which  is
       the first Monday in September.  You could use:

            # Note: SATISFY 1 is an idiom for "do nothing"
            REM Mon 1 Sept SATISFY 1
            OMIT [trigdate()]

       CAVEAT:  This  only  omits  the  next Labour Day, not all Labour Days in the future.  This
       could cause strange results, as the OMIT context can change depending on the current date.
       For example, if you use the following command after the above commands:

            REM Mon AFTER msg hello

       the  result will not be as you expect.  Consider producing a calendar for September, 1992.
       Labour Day was on Monday,  7  September,  1992.   However,  when  Remind  gets  around  to
       calculating  the  trigger  for  Tuesday,  8  September, 1992, the OMIT command will now be
       omitting Labour Day for 1993, and the "Mon AFTER" command will not be triggered.  (But see
       the description of SCANFROM in the section "DETAILS ABOUT TRIGGER COMPUTATION.")

       It  is  probably best to stay away from computing OMIT trigger dates unless you keep these
       pitfalls in mind.

       For versions of Remind starting from 03.00.07, you can include a MSG, RUN, etc. clause  in
       a SATISFY clause as follows:

            REM trigger_stuff SATISFY [expr] MSG body

       Note  that for this case only, the expr after SATISFY must be enclosed in square brackets.
       It must come after all the other components of the trigger,  and  immediately  before  the
       MSG, RUN, etc. keyword.  If expr cannot be satisfied, then the reminder is not triggered.

       Thus, the "Friday the 13th" example can be expressed more compactly as:

            REM 13 +2 SATISFY [$Tw == 5] MSG Friday the 13th is %b.

       And  you  can  trigger  a  reminder on Mondays, Wednesdays and Thursdays occurring on odd-
       numbered days of the month with the following:

            REM Mon Wed Thu SATISFY [$Td %2 ] MSG Here it is!!!

       Note that SATISFY and OMITFUNC can often be used to solve  the  same  problem,  though  in
       different  ways.  Sometimes a SATISFY is cleaner and sometimes an OMITFUNC; experiment and
       use whichever seems clearer.

POSSIBLY-UNCOMPUTABLE TRIGGERS

       Occasionally, you may wish to suppress the "Can't compute trigger" warnings for  reminders
       for  which  a  trigger  date  cannot  be computed.  For example, the following reminder is
       triggered on a Monday that is not a holiday if the following Tuesday is a holiday:

               REM Mon SKIP SATISFY [isomitted($T+1)] MSG Work between holidays

       However, if there are no Mondays after today's date that  satisfy  the  condition,  Remind
       will  print  the  "Can't  compute  trigger"  error.   To  suppress  this,  use  the MAYBE-
       UNCOMPUTABLE keyword:

               REM MAYBE-UNCOMPUTABLE Mon SKIP SATISFY [isomitted($T+1)] MSG Work between holidays

       It's almost never appropriate to use MAYBE-UNCOMPUTABLE, but it is provided for those rare
       occasions  when  it  makes  sense.   If  you  use MAYBE-UNCOMPUTABLE inside the evaltrig()
       function, then untriggerable triggers return -1.  For example:

               SET a evaltrig("MAYBE-UNCOMPUTABLE Mon SKIP OMIT Mon")

       will set a to -1.

DEBUGGING REMINDER SCRIPTS

       Although the command-line -d option is useful for debugging, it is  often  overkill.   For
       example,  if you turn on the -dx option for a reminder file with many complex expressions,
       you'll get a huge amount of output.  The DEBUG command allows you to control the debugging
       flags under program control.  The format is:

       DEBUG [+flagson] [-flagsoff]

       Flagson  and flagsoff consist of strings of the characters "extvlf" that correspond to the
       debugging options discussed in the command-line options section.  If preceded with a  "+",
       the corresponding group of debugging options is switched on.  Otherwise, they are switched
       off.  For example, you could use this sequence to debug a complicated expression:

            DEBUG +x
            set a very_complex_expression(many_args)
            DEBUG -x

       THE DUMPVARS COMMAND

       The command DUMPVARS displays the values of variables in memory.  Its format is:

       DUMPVARS [var...]

       If you supply a space-separated list of variable names, the  corresponding  variables  are
       displayed.   If  you  do  not supply a list of variables, then all variables in memory are
       displayed.  To dump a system variable, put its name in the list of variables to dump.   If
       you  put  a  lone  dollar sign in the list of variables to dump, then all system variables
       will be dumped.

       THE ERRMSG COMMAND

       The ERRMSG command has the following format:

       ERRMSG body

       The body is passed through the substitution filter  (with  an  implicit  trigger  date  of
       today()) and printed to the error output stream.  Example:

            IF !defined("critical_var")
                 ERRMSG You must supply a value for "critical_var"
                 EXIT
            ENDIF

       THE EXIT COMMAND

       The  above  example  also shows the use of the EXIT command.  This causes an unconditional
       exit from script processing.  Any queued timed reminders are discarded.   If  you  are  in
       calendar mode (described next), then the calendar processing is aborted.

       If you supply an INT-type expression after the EXIT command, it is returned to the calling
       program as the exit status.  Otherwise, an exit status of 99 is returned.

       THE FLUSH COMMAND

       This command simply consists of the word FLUSH on a line by itself.  The  command  flushes
       the  standard  output  and  standard  error  streams used by Remind.  This is not terribly
       useful to most people, but may be useful if you run Remind  as  a  subprocess  of  another
       program, and want to use pipes for communication.

CALENDAR MODE

       If  you  supply the -c, -s or -p command-line option, then Remind runs in "calendar mode."
       In this mode, Remind interprets the script repeatedly, performing  one  iteration  through
       the whole file for each day in the calendar.  Reminders that trigger are saved in internal
       buffers, and then inserted into the calendar in the appropriate places.

       If you also supply the -a option, then Remind will not  include  timed  reminders  in  the
       calendar.

       The  -p  option  is  used  in conjunction with the Rem2PS program to produce a calendar in
       PostScript format.  For example, the  following  command  will  send  PostScript  code  to
       standard output:

            remind -p .reminders | rem2ps

       You can print a PostScript calendar by piping this to the lpr command.

       If you have a reminder script called ".reminders", and you execute this command:

            remind -c .reminders jan 1993

       then  Remind  executes  the  script  31 times, once for each day in January.  Each time it
       executes the script, it increments the value of today().  Any reminders whose trigger date
       matches today() are entered into the calendar.

       MSG and CAL-type reminders, by default, have their entire body inserted into the calendar.
       RUN-type reminders are not normally inserted into the calendar.  However, if you enclose a
       portion  of the body in the %"...%" sequence, only that portion is inserted.  For example,
       consider the following:

            REM 6 Jan MSG %"Dianne's birthday%" is %b

       In the normal mode, Remind  would  print  "Dianne's  birthday  is  today"  on  6  January.
       However,  in the calendar mode, only the text "Dianne's birthday" is inserted into the box
       for 6 January.

       If you explicitly use the %"...%" sequence in a RUN-type reminder, then the  text  between
       the  delimiters  is  inserted into the calendar.  If you use the sequence %"%" in a MSG or
       CAL-type reminder, then no calendar entry is produced for that reminder.

       PRESERVING VARIABLES

       Because Remind iterates through the script for each day in the calendar,  slow  operations
       may severely reduce the speed of producing a calendar.

       For example, suppose you set the variables "me" and "hostname" as follows:

            SET me shell("whoami")
            SET hostname shell("hostname")

       Normally,  Remind  clears  all variables between iterations in calendar mode.  However, if
       certain variables are slow to compute, and will not change  between  iterations,  you  can
       "preserve"  their  values with the PRESERVE command.  Also, since function definitions are
       preserved between calendar  iterations,  there  is  no  need  to  redefine  them  on  each
       iteration.  Thus, you could use the following sequence:

            IF ! defined("initialized")
                 set initialized 1
                 set me shell("whoami")
                 set hostname shell("hostname")
                 fset func(x) complex_expr
                 preserve initialized me hostname
            ENDIF

       The  operation is as follows:  On the first iteration through the script, "initialized" is
       not defined.  Thus, the commands between IF and ENDIF are executed.  The PRESERVE  command
       ensures  that  the  values  of  initialized,  me and hostname are preserved for subsequent
       iterations.  On the next iteration,  the  commands  are  skipped,  since  initialized  has
       remained  defined.   Thus,  time-consuming  operations  that do not depend on the value of
       today() are done only once.

       Most system variables (those whose names  start  with  '$')  are  automatically  preserved
       between calendar iterations.

       Note  that  for  efficiency, Remind caches the reminder script (and any INCLUDEd files) in
       memory when producing a calendar.

       Timed reminders are sorted and placed into the calendar in time order.  These are followed
       by  non-timed  reminders.   Remind automatically places the time of timed reminders in the
       calendar according to the -b command-line option.  Reminders in calendar mode  are  sorted
       as  if  the  -g  option  had  been used; you can change the sort order in calendar mode by
       explicitly using the -g option to specify a different order from the default.

       REPEATED EXECUTION

       If you supply a repeat parameter on the command line, and do not use the  -c,  -p,  or  -s
       options, Remind operates in a similar manner to calendar mode.  It repeatedly executes the
       reminder  script,  incrementing  today()  with  each  iteration.   The  same  rules  about
       preserving  variables  and  function  definitions  apply.   Note  that using repeat on the
       command line also enables the -q option and disables any -z option.  As an example, if you
       want to see how Remind will behave for the next week, you can type:

            remind .reminders '*7'

       If you want to print the dates of the next 1000 days, use:

            (echo 'banner %'; echo 'msg [today()]%') | remind - '*1000'

INITIALIZING VARIABLES ON THE COMMAND LINE

       The  -i  option is used to initialize variables on the Remind command line.  The format is
       -ivar=expr, where expr is any valid expression.  Note that you may have to use  quotes  or
       escapes  to  prevent the shell from interpreting special characters in expr.  You can have
       as many -i options as you want on the command line,  and  they  are  processed  in  order.
       Thus,  if  a  variable is defined in one -i option, it can be referred to by subsequent -i
       options.

       Note that if you supply a date on the command line, it is not  parsed  until  all  options
       have  been  processed.   Thus,  if  you  use today() in any of the -i expressions, it will
       return the same value as realtoday() and not the date supplied on the command line.

       Any variables defined on the command line are preserved as with the PRESERVE command.

       You should not have any spaces between the  -i  option  and  the  equal  sign;  otherwise,
       strange variable names are created that can only be accessed with the value() or defined()
       functions.

       You can also define a function on the command line by using:

       -ifunc(args)=definition

       Be sure to protect special characters from shell interpretation.

MORE ABOUT POSTSCRIPT

       The PS and PSFILE reminders pass PostScript code directly to the printer.  They differ  in
       that  the  PS-type  reminder  passes  its  body  directly  to the PostScript output (after
       processing by the substitution filter) while the PSFILE-type's body should simply  consist
       of  a  filename.  The Rem2PS program will open the file named in the PSFILE-type reminder,
       and include its contents in the PostScript output.

       The PostScript-type reminders for a particular day are included in the  PostScript  output
       in  sorted  order  of  priority.   Note  that the order of PostScript commands has a major
       impact on the appearance of the calendars.   For  example,  PostScript  code  to  shade  a
       calendar  box will obliterate code to draw a moon symbol if the moon symbol code is placed
       in the calendar first.  For  this  reason,  you  should  not  provide  PS  or  PSFILE-type
       reminders  with  priorities;  instead,  you should ensure that they appear in the reminder
       script in the correct order.   PostScript  code  should  draw  objects  working  from  the
       background to the foreground, so that foreground objects properly overlay background ones.
       If you prioritize these reminders and run the  script  using  descending  sort  order  for
       priorities, the PostScript output will not work.

       All  of  the  PostScript  code  for  a particular date is enclosed in a save-restore pair.
       However, if several PostScript-type reminders are triggered for a single day, each section
       of  PostScript  is  not  enclosed  in  a  save-restore  pair - instead, the entire body of
       included PostScript is enclosed.

       PostScript-type reminders are executed  by  the  PostScript  printer  before  any  regular
       calendar  entries.   Thus,  regular  calendar  entries  will  overlay  the PostScript-type
       reminders, allowing you to create shaded or graphical backgrounds for particular days.

       Before executing your PostScript code, the origin of the PostScript coordinate  system  is
       positioned  to  the  bottom  left-hand  corner  of  the "box" in the calendar representing
       today().  This location is exactly in the middle of the intersection  of  the  bottom  and
       left  black lines delineating the box - you may have to account for the thickness of these
       lines when calculating positions.

       Several PostScript variables are  available  to  the  PostScript  code  you  supply.   All
       distance and size variables are in PostScript units (1/72 inch.)  The variables are:

       LineWidth
              The width of the black grid lines making up the calendar.

       Border The  border  between  the  center  of  the  grid  lines and the space used to print
              calendar entries.  This border is normally blank space.

       BoxWidth and BoxHeight
              The width and height of the  calendar  box,  from  center-to-center  of  the  black
              gridlines.

       InBoxHeight
              The  height  from the center of the bottom black gridline to the top of the regular
              calendar entry area.  The space from here to the top of the box  is  used  only  to
              draw the day number.

       /DayFont, /EntryFont, /SmallFont, /TitleFont and /HeadFont
              The  fonts used to draw the day numbers, the calendar entries, the small calendars,
              the calendar title (month, year) and the day-of-the-week headings, respectively.

       DaySize, EntrySize, TitleSize and HeadSize
              The sizes of the above fonts.  (The size of the small calendar font is not  defined
              here.)  For example, if you wanted to print the Hebrew date next to the regular day
              number in the calendar, use:

            REM PS Border BoxHeight Border sub DaySize sub moveto \
               /DayFont findfont DaySize scalefont setfont \
               ([hebday(today())] [hebmon(today())]) show

              Note how /DayFont and DaySize are used.

       Note that if you supply PostScript code, it is  possible  to  produce  invalid  PostScript
       files.   Always test your PostScript thoroughly with a PostScript viewer before sending it
       to the printer.  You should not use any document structuring comments in  your  PostScript
       code.

DAEMON MODE

       If you use the -z command-line option, Remind runs in the "daemon" mode.  In this mode, no
       "normal" reminders are issued.  Instead, only timed reminders are  collected  and  queued,
       and are then issued whenever they reach their trigger time.

       In  addition,  Remind  wakes  up  every  few minutes to check the modification date on the
       reminder script (the filename supplied on the command line.)  If Remind detects  that  the
       script  has  changed,  it  re-executes  itself  in daemon mode, and interprets the changed
       script.

       In daemon mode, Remind also re-reads the remind script when it  detects  that  the  system
       date has changed.

       In  daemon  mode,  Remind  acts as if the -f option had been used, so to run in the daemon
       mode in the background, use:

            remind -z .reminders &

       If you use sh or bash, you may have to use the "nohup" command to ensure that  the  daemon
       is not killed when you log out.

PURGE MODE

       If  you  supply  the  -j command-line option, Remind runs in purge mode.  In this mode, it
       tries to purge expired reminders from your reminder files.

       In purge mode, Remind reads your reminder  file  and  creates  a  new  file  by  appending
       ".purged"  to the original file name.  Note that Remind never edits your original file; it
       always creates a new .purged file.

       If you invoke Remind against a directory instead of a file, then a .purged file is created
       for each *.rem file in the directory.

       Normally, Remind does not create .purged files for INCLUDed files.  However, if you supply
       a numeric argument after -j, then Remind will create .purged files for the specified level
       of  INCLUDE.   For example, if you invoke Remind with the argument -j2, then .purged files
       will be created for the file (or directory) specified  on  the  command  line,  any  files
       included  by them, and any files included by those files.  However, .purged files will not
       be created for third-or-higher level INCLUDE files.

       Determining which reminders have expired is extremely tricky.  Remind does its  best,  but
       you should always compare the .purged file to the original file and hand-merge the changes
       back in.

       Remind annotates the .purged file as follows:

       An expired reminder is prefixed with:  #!P: Expired:

       In situations where Remind cannot reliably determine that something was expired,  you  may
       see the following comments inserted before the problematic line:

          #!P: Cannot purge SATISFY-type reminders

          #!P: The next IF evaluated false...
          #!P: REM statements in IF block not checked for purging.

          #!P: The previous IF evaluated true.
          #!P: REM statements in ELSE block not checked for purging

          #!P: The next IFTRIG did not trigger.
          #!P: REM statements in IFTRIG block not checked for purging.

          #!P: Next line has expired, but contains expression...  please verify

          #!P: Next line may have expired, but contains non-constant expression

          #!P! Could not parse next line: Some-Error-Message-Here

       Remind  always annotates .purged files with lines beginning with "#!P".  If such lines are
       encountered in the original file, they are not copied to the .purged file.

SORTING REMINDERS

       The -g option causes Remind to sort reminders by trigger date, time  and  priority  before
       issuing  them.   Note  that reminders are still calculated in the order encountered in the
       script.  However, rather than being issued immediately, they  are  saved  in  an  internal
       buffer.   When Remind has finished processing the script, it issues the saved reminders in
       sorted order.  The -g option can be followed by up to four characters that must all be "a"
       or  "d".   The  first  character  specifies  the  sort order by trigger date (ascending or
       descending), the second specifies the sort order by trigger time and the  third  specifies
       the  sort  order  by  priority.  If the fourth character is "d", the untimed reminders are
       sorted before timed reminders.  The default is to sort all fields in ascending  order  and
       to sort untimed reminders after timed reminders.

       In  ascending  order, reminders are issued with the most imminent first.  Descending order
       is the reverse.  Reminders are always sorted by trigger date, and reminders with the  same
       trigger  date  are  then  sorted by trigger time.  If two reminders have the same date and
       time, then the priority is used to break ties.  Reminders with the  same  date,  time  and
       priority are issued in the order they were encountered.

       You  can  define  a  user-defined  function  called  SORTBANNER  that  takes one DATE-type
       argument.  In sort mode, the following sequence happens:

       If Remind notices that the next reminder to issue has a different trigger  date  from  the
       previous  one (or if it is the first one to be issued), then SORTBANNER is called with the
       trigger date as its argument.  The result is coerced to a string, and passed  through  the
       substitution filter with the appropriate trigger date.  The result is then displayed.

       Here's an example - consider the following fragment:

            # Switch off the normal banner
            BANNER %
            REM 11 March 1993 ++1 MSG Not so important
            REM 17 March 1993 ++7 MSG Way in the future
            REM 10 March 1993 MSG Important Reminder
            REM 11 March 1993 ++1 MSG Not so important - B
            FSET sortbanner(x) iif(x == today(), \
                 "***** THINGS TO DO TODAY *****", \
                 "----- Things to do %b -----")

       Running this with the -gaa option on 10 March 1993 produces the following output:

            ***** THINGS TO DO TODAY *****

            Important Reminder

            ----- Things to do tomorrow -----

            Not so important

            Not so important - B

            ----- Things to do in 7 days' time -----

            Way in the future

       You  can  use the args() built-in function to determine whether or not SORTBANNER has been
       defined.  (This could be used, for example, to provide a default definition for SORTBANNER
       in a system-wide file included at the end of the user's file.)  Here's an example:

            # Create a default sortbanner function if it hasn't already
            # been defined
            if args("sortbanner") != 1
                 fset sortbanner(x) "--- Things to do %b ---"
            endif

MSGPREFIX() AND MSGSUFFIX()

       You  can  define  two  functions  in your script called msgprefix() and msgsuffix().  They
       should each accept one argument, a number from 0 to 9999.

       In normal mode, for MSG- and MSF-type reminders, the following sequence occurs when Remind
       triggers a reminder:

       o      If msgprefix() is defined, it is evaluated with the priority of the reminder as its
              argument.  The result is printed.   It  is  not  passed  through  the  substitution
              filter.

       o      The body of the reminder is printed.

       o      If msgsuffix() is defined, it is evaluated with the priority of the reminder as its
              argument.  The result is printed.   It  is  not  passed  through  the  substitution
              filter.

       Here's an example:  The following definition causes priority-0 reminders to be preceded by
       "URGENT", and priority-6000 reminders to be preceded by "(not important)".

            fset msgprefix(x) iif(x==0, "URGENT: ", \
                 x==6000, "(not important) ", "")

       In Calendar Mode (with the -c, -s or -p options), an analogous  pair  of  functions  named
       calprefix()  and calsuffix() can be defined.  They work with all reminders that produce an
       entry in the calendar (i.e., CAL- and possibly RUN-type  reminders  as  well  as  MSG-type
       reminders.)

       NOTES

       Normally,  the  body of a reminder is followed by a carriage return.  Thus, the results of
       msgsuffix() will appear on the next line.  If you don't want this, end  the  body  of  the
       reminder  with a percentage sign, "%".  If you want a space between your reminders, simply
       include a carriage return (char(13)) as part of the msgsuffix() return value.

       If Remind has problems evaluating msgprefix(), msgsuffix() or sortbanner(), you will see a
       lot of error messages.  For an example of this, define the following:

            fset msgprefix(x) x/0

SUPPORT FOR OTHER LANGUAGES

       Your  version  of  Remind may have been compiled to support a language other than English.
       This support may or may not be complete - for example, all error and  usage  messages  may
       still  be  in  English.  However, at a minimum, non-English versions of Remind will output
       names of months and weekdays in the selected language.  Also, the  substitution  mechanism
       will substitute constructs suitable for the selected language rather than for English.

       Note  that  a non-English version of Remind will accept only English names of weekdays and
       months in a reminder script.

       If there is no support for your particular language, you can set Remind  system  variables
       so  that  calendars  are  printed  using  your language's day and month names.  The system
       variables that you can set are:

       $Monday, $Tuesday, $Wednesday, $Thursday, $Friday, $Saturday
              Set each of these system variables to a string representing the corresponding day's
              name in your language.  Strings must be valid UTF-8 strings.

       $January,  $February,  $March,  $April, $May, $June, $July, $August, $September, $October,
       $November, $December
              Set each of these system variables  to  a  string  representing  the  corresponding
              month's name in your language.  Strings must be valid UTF-8 strings.

       Note  that  if  you  set  the day- or month-name system variables, they should be set in a
       section of your script that always is evaluated.  If you set them inside an IF  statement,
       for example, results are unpredictable.

       Note  also  that  the Rem2PS back-end does not support the full range of UTF-8 characters.
       The TkRemind, rem2html and rem2pdf back-ends all do support the full UTF-8 range.

THE HEBREW CALENDAR

       Remind has support for the Hebrew calendar, which is a luni-solar calendar.   This  allows
       you  to  create  reminders  for  Jewish  holidays, jahrzeits (anniversaries of deaths) and
       smachot (joyous occasions.)

       THE HEBREW YEAR

       The Hebrew year has 12 months, alternately 30 and 29 days long.  The months are:  Tishrey,
       Heshvan,  Kislev, Tevet, Shvat, Adar, Nisan, Iyar, Sivan, Tamuz, Av and Elul.  In Biblical
       times, the year started in Nisan, but Rosh Hashana (Jewish New Year) is now celebrated  on
       the 1st and 2nd of Tishrey.

       In  a cycle of 19 years, there are 7 leap years, being years 3, 6, 8, 11, 14, 17 and 19 of
       the cycle.  In a leap year, an extra month of 30 days is added before Adar.  The two Adars
       are called Adar A and Adar B.

       For certain religious reasons, the year cannot start on a Sunday, Wednesday or Friday.  To
       adjust for this, a day is taken off Kislev or added to Heshvan.  Thus, a regular year  can
       have from 353 to 355 days, and a leap year from 383 to 385.

       When  Kislev or Heshvan is short, it is called chaser, or lacking.  When it is long, it is
       called shalem, or full.

       The Jewish date changes at sunset.  However, Remind will change the date at midnight,  not
       sunset.   So  in the period between sunset and midnight, Remind will be a day earlier than
       the true Jewish date.  This should not be much of a problem in practice.

       The computations for the Jewish calendar were based on the program "hdate" written by Amos
       Shapir  of  the  Hebrew  University  of Jerusalem, Israel.  He also supplied the preceding
       explanation of the calendar.

       HEBREW DATE FUNCTIONS

       hebday(d_date)
              Returns the day of the Hebrew month  corresponding  to  the  date  parameter.   For
              example,  12  April  1993 corresponds to 21 Nisan 5753.  Thus, hebday('1993/04/12')
              returns 21.

       hebmon(d_date)
              Returns the  name  of  the  Hebrew  month  corresponding  to  date.   For  example,
              hebmon('1993/04/12') returns "Nisan".

       hebyear(d_date)
              Returns  the Hebrew year corresponding to date.  For example, hebyear('1993/04/12')
              returns 5753.

       hebdate(i_day, s_hebmon [,id_yrstart [,i_jahr [,i_aflag]]])
              The hebdate() function is the most complex of the Hebrew support functions.  It can
              take from 2 to 5 arguments.  It returns a DATE corresponding to the Hebrew date.

              The  day  parameter  can  range  from  1 to 30, and specifies the day of the Hebrew
              month.  The hebmon parameter is a string that must name one of  the  Hebrew  months
              specified  above.   Note  that  the  month must be spelled out in full, and use the
              English transliteration shown previously.  You can also specify "Adar A" and  "Adar
              B."  Month names are not case-sensitive.

              The  yrstart  parameter  can either be a DATE or an INT.  If it is a DATE, then the
              hebdate() scans for the first Hebrew date on or after that date.  For example:

                        hebdate(15, "Nisan", '1990/01/01')

              returns 1990/03/30, because that is the first occurrence of 15 Nisan on or after  1
              January 1990.

              If yrstart is an INT, it is interpreted as a Hebrew year.  Thus:

                        hebdate(22, "Kislev", 5756)

              returns  1995/12/15,  because  that date corresponds to 22 Kislev, 5756.  Note that
              none of the Hebrew date functions will work  with  dates  outside  Remind's  normal
              range for dates.

              If yrstart is not supplied, it defaults to today().

              The jahr modifies the behaviour of hebdate() as follows:

              If  jahr  is  0  (the default), then hebdate() keeps scanning until it finds a date
              that exactly satisfies the other parameters.  For example:

                        hebdate(30, "Adar A", 1993/01/01)

              returns 1995/03/02, corresponding to 30 Adar A, 5755,  because  that  is  the  next
              occurrence  of  30 Adar A after 1 January, 1993.  This behaviour is appropriate for
              Purim Katan, which only appears in leap years.

              If jahr is 1, then the date is modified as follows:

              o      30 Heshvan is converted to 1 Kislev in years when Heshvan is chaser

              o      30 Kislev is converted to 1 Tevet in years when Kislev is chaser

              o      30 Adar A is converted to 1 Nisan in non-leapyears

              o      Other dates in Adar A are moved to the corresponding day  in  Adar  in  non-
                     leapyears

              This behaviour is appropriate for smachot (joyous occasions) and for some jahrzeits
              - see "JAHRZEITS."

              if jahr is 2, then the date is modified as follows:

              o      30 Kislev and 30  Heshvan  are  converted  to  29  Kislev  and  29  Heshvan,
                     respectively, if the month is chaser

              o      30 Adar A is converted to 30 Shvat in non-leapyears

              o      Other  dates  in  Adar  A are moved to the corresponding day in Adar in non-
                     leapyears

              if jahr is not 0, 1, or 2, it is interpreted as a Hebrew year, and the behaviour is
              calculated as described in the next section, "JAHRZEITS."

              The aflag parameter modifies the behaviour of the function for dates in Adar during
              leap years.  The aflag is only used if yrstart is a DATE type.

              The aflag only affects date calculations if hebmon is specified as "Adar".  In leap
              years, the following algorithm is followed:

              o      If aflag is 0, then the date is triggered in Adar B.  This is the default.

              o      If  aflag  is  1,  then  the  date  is  triggered  in  Adar  A.  This may be
                     appropriate for jahrzeits in the Ashkenazi tradition; consult a rabbi.

              o      If aflag is 2, then the date is triggered in both Adar A and  Adar  B  of  a
                     leap year.  Some Ashkenazim perform jahrzeit in both Adar A and Adar B.

       JAHRZEITS

       A  jahrzeit  is a yearly commemoration of someone's death.  It normally takes place on the
       anniversary of the death, but may be delayed if burial is delayed - consult  a  rabbi  for
       more information.

       In  addition,  because  some  months  change  length,  it  is  not  obvious  which day the
       anniversary of a death is.  The following rules are used:

       o      If the death occurred on 30 Heshvan, and Heshvan in the year  after  the  death  is
              chaser,  then  the  jahrzeit  is  observed  on  29 Heshvan in years when Heshvan is
              chaser.  Otherwise, the yahrzeit is observed on 1 Kislev when Heshvan is chaser.

       o      If the death occurred on 30 Kislev, and Kislev in  the  year  after  the  death  is
              chaser,  then the jahrzeit is observed on 29 Kislev in years when Kislev is chaser.
              Otherwise, the yahrzeit is observed on 1 Tevet when Kislev is chaser.

       o      If the death occurred on 1-29 Adar A, it is observed on 1-29 Adar in non-leapyears.

       o      If the death occurred on 30 Adar A, it is observed on 30 Shvat in a non-leapyear.

       Specifying a Hebrew year for the  jahr  parameter  causes  the  correct  behaviour  to  be
       selected  for a death in that year.  You may also have to specify aflag, depending on your
       tradition.

       The jahrzeit information was supplied by  Frank  Yellin,  who  quoted  "The  Comprehensive
       Hebrew  Calendar"  by  Arthur  Spier, and "Calendrical Calculations" by E. M. Reingold and
       Nachum Dershowitz.

OUT-OF-BAND REMINDERS

       The SPECIAL keyword is used to transmit "out-of-band" information to Remind backends, such
       as  tkremind or Rem2PS.  They are used only when piping data from a remind -p line.  (Note
       that the COLOR special is an exception; it downgrades to the equivalent of MSG in remind's
       normal mode of operation.)

       The  various  SPECIALs recognized are particular for each backend; however, there are four
       SPECIALs that all backends should attempt to support.  They  are  currently  supported  by
       Rem2PS, tkremind and rem2html.

       The SHADE special replaces the psshade() function.  Use it like this:
            REM Sat Sun SPECIAL SHADE 128
            REM Mon SPECIAL SHADE 255 0 0
       The  SHADE  keyword  is  followed  by  either one or three numbers, from 0 to 255.  If one
       number is supplied, it is interpreted as a grey-scale value from black (0) to white (255).
       If  three numbers are supplied, they are interpreted as RGB components from minimum (0) to
       maximum (255).  The example above shades weekends a fairly dark grey and makes  Mondays  a
       fully-saturated red.  (These shadings appear in calendars produced by Rem2PS, tkremind and
       rem2html.)

       The MOON special replaces the psmoon() function.  Use it like this:
            REM [moondate(0)] SPECIAL MOON 0
            REM [moondate(1)] SPECIAL MOON 1
            REM [moondate(2)] SPECIAL MOON 2
            REM [moondate(3)] SPECIAL MOON 3
       These draw little moons on the various calendars.  The complete syntax of the MOON special
       is as follows:
            ... SPECIAL MOON phase moonsize fontsize msg

       Phase  is  a  number from 0 to 3, with 0 representing a new moon, 1 the first quarter, 2 a
       full moon and 3 the last quarter.

       moonsize is the diameter in PostScript units of the moon to draw.  If omitted or  supplied
       as -1, the backend chooses an appropriate size.

       fontsize is the font size in PostScript units of the msg

       Msg is additional text that is placed near the moon glyph.

       Note  that  only the Rem2PS backend supports moonsize and fontsize; the other backends use
       fixed sizes.

       The COLOR special lets you place colored reminders in the calendar.  Use it like this:

            REM ... SPECIAL COLOR 255 0 0 This is a bright red reminder
            REM ... SPECIAL COLOR 0 128 0 This is a dark green reminder

       You can spell COLOR either the American way ("COLOR") or the British way ("COLOUR").  This
       manual will use the American way.

       Immediately  following  COLOR  should  be  three  decimal  numbers  ranging  from 0 to 255
       specifying red, green and blue intensities, respectively.  The rest of  the  line  is  the
       text to put in the calendar.

       The COLOR special is "doubly special", because in its normal operating mode, remind treats
       a COLOR special just like a MSG-type reminder.  Also, if you  invoke  Remind  with  -@[n],
       then it approximates SPECIAL COLOR reminders on your terminal.

       See  also  the  documentation  of the $DefaultColor system variable in the section "SYSTEM
       VARIABLES".

       The WEEK special lets you place annotations such as the week number in the calendar.   For
       example,  this would number each Monday with the ISO 8601 week number.  The week number is
       shown like this: "(Wn)" in this example, but you can put whatever text you like after  the
       WEEK keyword.

            REM Monday SPECIAL WEEK (W[weekno()])

MISCELLANEOUS

       COMMAND ABBREVIATIONS

       The following tokens can be abbreviated:

       o      REM can be omitted - it is implied if no other valid command is present.

       o      CLEAR-OMIT-CONTEXT --> CLEAR

       o      PUSH-OMIT-CONTEXT --> PUSH

       o      POP-OMIT-CONTEXT --> POP

       o      DUMPVARS --> DUMP

       o      BANNER --> BAN

       o      INCLUDE --> INC

       o      SCANFROM --> SCAN

       NIFTY EXAMPLES

       This section is a sampling of what you can do with Remind.

            REM 5 Feb 1991 AT 14:00 +45 *30 \
            RUN mail -s "Meeting at %2" $LOGNAME </dev/null &

       On  5  February,  1991, this reminder will mail you reminders of a 2:00pm meeting at 1:15,
       1:45 and 2:00.  The subject of the mail message will be "Meeting at 2:00pm" and  the  body
       of the message will be blank.

            REM AT 17:00 RUN echo "5:00pm - GO HOME!" | xless -g +0+0 &

       This  reminder  will  pop  up  an xless window at 5:00pm every day.  The xless window will
       contain the line "5:00pm - GO HOME!"

            REM AT 23:59 RUN (sleep 120; remind -a [filename()]) &

       This reminder will run at one minute to midnight.  It will cause a new Remind  process  to
       start  at one minute past midnight.  This allows you to have a continuous reminder service
       so you can work through the night and still get timed reminders for early in the  morning.
       Note that this trick is no longer necessary, providing you run Remind in daemon mode.

            remind -c12 /dev/null Jan 1993

       This  invocation  of  Remind  will cause it to print a calendar for 1993, with all entries
       left blank.

            REM CAL [trigdate()-date(year(trigdate()), 1, 1)+1]

       This example puts an entry in each box of a calendar showing the number (1-365 or 366)  of
       the day of the year.

            REM Tue 2 Nov SATISFY (year(trigdate())%4) == 0
            IF trigvalid()
                 REM [trigdate()] ++5 MSG \
                 U.S. Presidential Election!!
            ENDIF

       This example warns you 5 days ahead of each American presidential election.  The first REM
       command calculates the first Tuesday  after  the  first  Monday  in  November.   (This  is
       equivalent  to the first Tuesday on or after 2 November.)  The SATISFY clause ensures that
       the trigger date is issued only in election years, which are multiples of 4.   The  second
       REM command actually issues the reminder.

       DETAILS ABOUT TRIGGER COMPUTATION

       Here  is  a  conceptual  description  of  how  triggers  are calculated.  Note that Remind
       actually uses a much more efficient procedure, but the results are  the  same  as  if  the
       conceptual procedure had been followed.

       Remind  starts  from  the  current date (that is, the value of today()) and scans forward,
       examining each day one at a time until it finds a date that satisfies the trigger, or  can
       prove that no such dates (on or later than today()) exist.

       If  Remind  is  executing  a  SATISFY-type  reminder,  it  evaluates  the  expression with
       trigdate() set to the date found above.  If the expression evaluates to zero or  the  null
       string,  Remind  continues  the  scanning procedure described above, starting with the day
       after the trigger found above.

       The SCANFROM clause (having a syntax similar to UNTIL)  can  modify  the  search  strategy
       used.   In this case, Remind begins the scanning procedure at scan_date, which is the date
       specified in the SCANFROM clause.  For example:

            REM Mon 1 SCANFROM 17 Jan 1992 MSG Foo

       The example above will always have a trigger date of Monday, 3  February  1992.   That  is
       because Remind starts scanning from 17 January 1992, and stops scanning as soon as it hits
       a date that satisfies "Mon 1."

       The main use of SCANFROM is in situations where you want to  calculate  the  positions  of
       floating holidays.  Consider the Labour Day example shown much earlier.  Labour Day is the
       first Monday in September.  It can move over a range of 7 days.   Consider  the  following
       sequence:

            REM Mon 1 Sept SCANFROM [today()-7] ADDOMIT MSG Labour Day
            REM Mon AFTER MSG Hello

       The  SCANFROM clause makes sure that Remind begins scanning from 7 days before the current
       date.  This ensures that Labour Day for the current year will  continue  to  be  triggered
       until  7  days  after it has occurred.  This allows you to safely use the AFTER keyword as
       shown.

       As a special case, you can simply use a negative number after SCANFROM; a negative  number
       -N  is  interpreted  as  N  days  before  today.  Thus, the previous example could also be
       written like this:

            REM Mon 1 Sept SCANFROM -7 ADDOMIT MSG Labour Day
            REM Mon AFTER MSG Hello

       In general, use SCANFROM as shown for safe movable OMITs.  The amount you should scan back
       by  (7  days  in  the example above) depends on the number of possible consecutive OMITted
       days that may occur, and on the range of the movable holiday.  Generally, a value of 7  is
       safe.

       The  FROM clause operates almost like the counterpoint to UNTIL.  It prevents the reminder
       from triggering before the FROM date.  For example, the following reminder:

            REM Mon Thu FROM 23 Jul 2007 UNTIL 2 Aug 2007 MSG Test

       will trigger on Mondays and Thursdays between 23 July 2007 and 2 August 2007 inclusive.

       FROM is really just syntactic sugar; you could implement the reminder above as follows:

            REM Mon Thu SCANFROM [max(today(), '2007-07-23')] \
                   UNTIL 2 Aug 2007 MSG Test

       but that's a lot harder to read.  Internally, Remind treats FROM  exactly  as  illustrated
       using SCANFROM.  For that reason, you cannot use both FROM and SCANFROM.

       Note  that  if  you  use  one  REM  command  to  calculate  a  trigger  date, perform date
       calculations (addition or subtraction, for example) and then use the modified  date  in  a
       subsequent  REM  command,  the  results may not be what you intended.  This is because you
       have circumvented the normal scanning mechanism.  You should try  to  write  REM  commands
       that  compute  trigger  dates that can be used unmodified in subsequent REM commands.  The
       file "defs.rem" that comes with the Remind distribution contains examples.

       DETAILS ABOUT TRIGVALID()

       The trigvalid() function returns 1 if Remind could find a trigger date  for  the  previous
       REM  or IFTRIG command.  More specifically, it returns 1 if Remind finds a date not before
       the starting date of the scanning that satisfies the trigger.  In addition, there  is  one
       special case in which trigvalid() returns 1 and trigdate() returns a meaningful result:

       If  the  REM  or  IFTRIG command did not contain an UNTIL clause, and contained all of the
       day, month and year components, then Remind will correctly compute a trigger date, even if
       it  happens  to be before the start of scanning.  Note that this behaviour is not true for
       versions of Remind prior to 03.00.01.

AUTHOR

       Dianne Skoll <dianne@skoll.ca> wrote Remind.  The moon code was copied largely  unmodified
       from  "moontool" by John Walker.  The sunrise and sunset functions use ideas from programs
       by Michael Schwartz and Marc T. Kaufman.  The  Hebrew  calendar  support  was  taken  from
       "hdate"  by  Amos  Shapir.   OS/2  support  was done by Darrel Hankerson, Russ Herman, and
       Norman Walsh.  The supported languages and their translators are listed below.   Languages
       marked  "complete"  support  error  messages  and usage instructions in that language; all
       others only support the substitution filter mechanism and month/day names.

       German -- Wolfgang Thronicke

       Dutch -- Willem Kasdorp and Erik-Jan Vens

       Finnish -- Mikko Silvonen (complete)

       French -- Laurent Duperval (complete)

       Norwegian -- Trygve Randen

       Danish -- Mogens Lynnerup

       Polish -- Jerzy Sobczyk (complete)

       Brazilian Portuguese -- Marco Paganini (complete)

       Italian -- Valerio Aimale

       Romanian -- Liviu Daia

       Spanish -- Rafa Couto

       Icelandic -- Björn Davíðsson

BUGS

       There's no good reason why read-only system variables are not implemented as functions, or
       why functions like version(), etc.  are not implemented as read-only system variables.

       Hebrew dates in Remind change at midnight instead of sunset.

       Language  should be selectable at run-time, not compile-time.  Don't expect this to happen
       soon!

       Remind has some built-in limits (for example, number of global OMITs.)

BIBLIOGRAPHY

       Nachum Dershowitz and Edward M. Reingold,  "Calendrical  Calculations",  Software-Practice
       and Experience, Vol. 20(9), Sept. 1990, pp 899-928.

       L. E. Doggett, Almanac for computers for the year 1978, Nautical Almanac Office, USNO.

       Richard  Siegel  and  Michael  and  Sharon  Strassfeld,  The  First Jewish Catalog, Jewish
       Publication Society of America.

SEE ALSO

       rem(1), rem2ps(1), rem2pdf(1), tkremind(1), rem2html(1)