Provided by: nmh_1.3-1build1_amd64 bug

NAME

       mh-sequence - sequence specification for nmh message system

SYNOPSIS

       most nmh commands

DESCRIPTION

       A  sequence  (or  sequence set) is a symbolic name representing a message or collection of
       messages.  nmh has several internally defined sequences, as  well  as  allowing  users  to
       define their own sequences.

   Message Specification and Pre-Defined Message Sequences
       Most  nmh  commands  accept  a  `msg'  or  `msgs' specification, where `msg' indicates one
       message and `msgs' indicates one or more messages.  To designate a message,  you  may  use
       either its number (e.g., 1, 10, 234) or one of these “reserved” message names:

            Name      Description
            first     the first message in the folder
            last      the last message in the folder
            cur       the most recently accessed message
            prev      the message numerically preceding “cur”
            next      the message numerically following “cur”

       In  commands  that  take  a  `msg' argument, the default is “cur”.  As a shorthand, “.” is
       equivalent to “cur”.

       For example: In a folder containing five messages numbered 5, 10, 94, 177 and 325, “first”
       is 5 and “last” is 325.  If “cur” is 94, then “prev” is 10 and “next” is 177.

       The  word  `msgs'  indicates  that  one  or  more  messages  may  be  specified.   Such  a
       specification consists of one message  designation  or  of  several  message  designations
       separated  by  spaces.  A message designation consists either of a message name as defined
       above, or a message range.

       A message range is specified as “name1-name2”  or  “name:n”,  where  `name',  `name1'  and
       `name2' are message names, and `n' is an integer.

       The specification “name1-name2” designates all currently existing messages from `name1' to
       `name2' inclusive.  The “reserved” message name “all” is a shorthand for the message range
       “first-last”.

       The  specification  “name:n”  designates  up  to  `n' messages.  These messages start with
       `name' if `name' is a message number or one  of  the  reserved  names  “first”  “cur”,  or
       “next”, The messages end with `name' if `name' is “prev” or “last”.  The interpretation of
       `n' may be overridden by preceding `n' with a plus or minus sign; `+n' always means up  to
       `n'  messages  starting  with `name', and `-n' always means up to `n' messages ending with
       `name'.

       In commands which accept a  `msgs'  argument,  the  default  is  either  “cur”  or  “all”,
       depending  on  which  makes  more sense for each command (see the individual man pages for
       details).  Repeated specifications of the same message have the same effect  as  a  single
       specification of the message.

       There is also a special “reserved” message name “new” which is used by the mhpath command.

   User-Defined Message Sequences
       In  addition to the “reserved” (pre-defined) message names given above, nmh supports user-
       defined sequence names.  User-defined sequences allow the nmh user a tremendous amount  of
       power in dealing with groups of messages in the same folder by allowing the user to bind a
       group of messages to a meaningful symbolic name.

       The name used to denote a  message  sequence  must  consist  of  an  alphabetic  character
       followed  by  zero  or  more alphanumeric characters, and can not be one of the “reserved”
       message names above.  After defining a sequence, it can be used wherever  an  nmh  command
       expects a `msg' or `msgs' argument.

       Some  forms  of message ranges are allowed with user-defined sequences.  The specification
       “name:n” may be used, and it designates up to the first `n' messages (or last `n' messages
       for `-n') which are elements of the user-defined sequence `name'.

       The  specifications  “name:next”  and “name:prev” may also be used, and they designate the
       next or previous message (relative to the current message) which  is  an  element  of  the
       user-defined  sequence  `name'.   The  specifications  “name:first”  and  “name:last”  are
       equivalent to “name:1” and “name:-1”, respectively.  The specification “name:cur”  is  not
       allowed  (use  just  “cur”  instead).  The syntax of these message range specifications is
       subject to change in the future.

       User-defined sequence names are specific to each folder.  They are defined using the  pick
       and mark commands.

   Public and Private User-Defined Sequences
       There  are  two varieties of user-defined sequences: public and private.  Public sequences
       of a folder are accessible to any nmh user that can read that folder.  They  are  kept  in
       each  folder  in  the  file  determined  by  the  “mh-sequences” profile entry (default is
       .mh_sequences).  Private sequences are accessible only to the nmh user that defined  those
       sequences and are kept in the user's nmh context file.

       In  general, the commands that create sequences (such as pick and mark) will create public
       sequences if the folder for which the sequences are being defined is writable by  the  nmh
       user.   For  most  commands,  this  can  be  overridden  by using the switches -public and
       -private.  But if the folder is read-only, or  if  the  “mh-sequences”  profile  entry  is
       defined but empty, then private sequences will be created instead.

   Sequence Negation
       Nmh  provides  the ability to select all messages not elements of a user-defined sequence.
       To do this, the user should define the entry “Sequence-Negation” in the nmh profile  file;
       its value may be any string.  This string is then used to preface an existing user-defined
       sequence name.  This specification then refers to  those  messages  not  elements  of  the
       specified sequence name.  For example, if the profile entry is:

            Sequence-Negation: not

       then  anytime  an  nmh  command  is given “notfoo” as a `msg' or `msgs' argument, it would
       substitute all messages that are not elements of the sequence “foo”.

       Obviously, the user should beware of defining sequences with names  that  begin  with  the
       value of the “Sequence-Negation” profile entry.

   The Previous Sequence
       Nmh  provides  the  ability  to remember the `msgs' or `msg' argument last given to an nmh
       command.  The entry “Previous-Sequence” should be defined in the nmh  profile;  its  value
       should  be  a sequence name or multiple sequence names separated by spaces.  If this entry
       is defined, when when an nmh command finishes, it will define the sequence(s) named in the
       value  of  this  entry  to be those messages that were specified to the command.  Hence, a
       profile entry of

            Previous-Sequence: pseq

       directs any nmh command that accepts a `msg' or `msgs' argument  to  define  the  sequence
       “pseq” as those messages when it finishes.

       Note: there can be a performance penalty in using the “Previous-Sequence” facility.  If it
       is used, all nmh programs have to write the sequence information to the .mh_sequences file
       for  the  folder  each  time  they  run.   If the “Previous-Sequence” profile entry is not
       included, only pick and mark will write to the .mh_sequences file.

   The Unseen Sequence
       Finally, many users like to indicate which messages have not been previously seen by them.
       The   commands   inc,   rcvstore,   show,  mhshow,  and  flist  honor  the  profile  entry
       “Unseen-Sequence” to support this activity.  This  entry  in  the  .mh_profile  should  be
       defined  as  one  or  more  sequence  names  separated by spaces.  If there is a value for
       “Unseen-Sequence” in the profile, then whenever new messages are placed in a folder (using
       inc  or  rcvstore), the new messages will also be added to all the sequences named in this
       profile entry.  For example, a profile entry of

            Unseen-Sequence: unseen

       directs inc to add new messages to the sequence “unseen”.   Unlike  the  behavior  of  the
       “Previous-Sequence”  entry  in the profile, however, the sequence(s) will not be zeroed by
       inc.

       Similarly, whenever show, mhshow, next, or prev displays a message, that message  will  be
       removed from any sequences named by the “Unseen-Sequence” entry in the profile.

FILES

       $HOME/.mh_profile          The user profile
       <mh-dir>/context           The user context
       <folder>/.mh_sequences     File for public sequences

PROFILE COMPONENTS

       mh-sequences:        Name of file to store public sequences
       Sequence-Negation:   To designate messages not in a sequence
       Previous-Sequence:   The last message specification given
       Unseen-Sequence:     Those messages not yet seen by the user

SEE ALSO

       flist(1), mark(1), pick(1), mh-profile(5)

DEFAULTS

       None