Provided by: man-db_2.8.3-2ubuntu0.1_amd64 bug

NAME

       man - an interface to the on-line reference manuals

SYNOPSIS

       man   [-C   file]   [-d]  [-D]  [--warnings[=warnings]]  [-R  encoding]  [-L  locale]  [-m
       system[,...]]  [-M  path]  [-S   list]   [-e   extension]   [-i|-I]   [--regex|--wildcard]
       [--names-only]  [-a]  [-u]  [--no-subpages]  [-P  pager]  [-r  prompt]  [-7] [-E encoding]
       [--no-hyphenation]  [--no-justification]  [-p  string]  [-t]  [-T[device]]   [-H[browser]]
       [-X[dpi]] [-Z] [[section] page[.section] ...] ...
       man -k [apropos options] regexp ...
       man -K [-w|-W] [-S list] [-i|-I] [--regex] [section] term ...
       man -f [whatis options] page ...
       man  -l  [-C  file] [-d] [-D] [--warnings[=warnings]] [-R encoding] [-L locale] [-P pager]
       [-r prompt] [-7] [-E encoding] [-p string] [-t] [-T[device]] [-H[browser]] [-X[dpi]]  [-Z]
       file ...
       man -w|-W [-C file] [-d] [-D] page ...
       man -c [-C file] [-d] [-D] page ...
       man [-?V]

DESCRIPTION

       man is the system's manual pager.  Each page argument given to man is normally the name of
       a program, utility or function.  The manual page associated with each of  these  arguments
       is then found and displayed.  A section, if provided, will direct man to look only in that
       section of the manual.  The default action is to search in all of the  available  sections
       following  a  pre-defined  order ("1 n l 8 3 2 3posix 3pm 3perl 3am 5 4 9 6 7" by default,
       unless overridden by the SECTION directive in /etc/manpath.config), and to show  only  the
       first page found, even if page exists in several sections.

       The  table  below  shows  the section numbers of the manual followed by the types of pages
       they contain.

       1   Executable programs or shell commands
       2   System calls (functions provided by the kernel)
       3   Library calls (functions within program libraries)
       4   Special files (usually found in /dev)
       5   File formats and conventions eg /etc/passwd
       6   Games
       7   Miscellaneous (including macro packages and conventions), e.g. man(7), groff(7)
       8   System administration commands (usually only for root)
       9   Kernel routines [Non standard]

       A manual page consists of several sections.

       Conventional section names include NAME, SYNOPSIS,  CONFIGURATION,  DESCRIPTION,  OPTIONS,
       EXIT STATUS,  RETURN VALUE,  ERRORS,  ENVIRONMENT,  FILES, VERSIONS, CONFORMING TO, NOTES,
       BUGS, EXAMPLE, AUTHORS, and SEE ALSO.

       The following conventions apply to the SYNOPSIS section and can be  used  as  a  guide  in
       other sections.

       bold text          type exactly as shown.
       italic text        replace with appropriate argument.
       [-abc]             any or all arguments within [ ] are optional.
       -a|-b              options delimited by | cannot be used together.
       argument ...       argument is repeatable.
       [expression] ...   entire expression within [ ] is repeatable.

       Exact  rendering  may vary depending on the output device.  For instance, man will usually
       not be able to render  italics  when  running  in  a  terminal,  and  will  typically  use
       underlined or coloured text instead.

       The  command  or  function  illustration  is  a  pattern  that  should  match all possible
       invocations.  In some cases it is advisable to illustrate several exclusive invocations as
       is shown in the SYNOPSIS section of this manual page.

EXAMPLES

       man ls
           Display the manual page for the item (program) ls.

       man man.7
           Display the manual page for macro package man from section 7.

       man -a intro
           Display,  in  succession, all of the available intro manual pages contained within the
           manual.  It is possible to quit between successive displays or skip any of them.

       man -t alias | lpr -Pps
           Format the manual page referenced by `alias', usually a shell manual  page,  into  the
           default troff or groff format and pipe it to the printer named ps.  The default output
           for groff is usually PostScript.  man --help should advise as to  which  processor  is
           bound to the -t option.

       man -l -Tdvi ./foo.1x.gz > ./foo.1x.dvi
           This  command will decompress and format the nroff source manual page ./foo.1x.gz into
           a device independent (dvi) file.  The redirection is necessary as the -T  flag  causes
           output  to  be  directed  to  stdout with no pager.  The output could be viewed with a
           program such as xdvi or further processed into PostScript  using  a  program  such  as
           dvips.

       man -k printf
           Search  the short descriptions and manual page names for the keyword printf as regular
           expression.  Print out any matches.  Equivalent to apropos printf.

       man -f smail
           Lookup the manual pages referenced by smail and print out the  short  descriptions  of
           any found.  Equivalent to whatis smail.

OVERVIEW

       Many  options are available to man in order to give as much flexibility as possible to the
       user.  Changes can be made to the search path, section order, output processor, and  other
       behaviours and operations detailed below.

       If  set, various environment variables are interrogated to determine the operation of man.
       It is possible to set the `catch all' variable $MANOPT  to  any  string  in  command  line
       format  with  the  exception  that any spaces used as part of an option's argument must be
       escaped (preceded by a backslash).  man will  parse  $MANOPT  prior  to  parsing  its  own
       command  line.  Those options requiring an argument will be overridden by the same options
       found on the command line.  To reset all  of  the  options  set  in  $MANOPT,  -D  can  be
       specified  as  the initial command line option.  This will allow man to `forget' about the
       options specified in $MANOPT although they must still have been valid.

       The manual pager utilities packaged as man-db make extensive use of index database caches.
       These  caches  contain  information  such  as  where  each manual page can be found on the
       filesystem and what its whatis (short one line description of the man page) contains,  and
       allow  man  to  run  faster  than if it had to search the filesystem each time to find the
       appropriate manual page.  If requested using the -u  option,  man  will  ensure  that  the
       caches  remain  consistent,  which can obviate the need to manually run software to update
       traditional whatis text databases.

       If man cannot find  a  mandb  initiated  index  database  for  a  particular  manual  page
       hierarchy,  it  will  still  search for the requested manual pages, although file globbing
       will be necessary to search within that hierarchy.  If whatis or apropos fails to find  an
       index it will try to extract information from a traditional whatis database instead.

       These  utilities  support compressed source nroff files having, by default, the extensions
       of .Z, .z and .gz.  It is possible to  deal  with  any  compression  extension,  but  this
       information  must  be known at compile time.  Also, by default, any cat pages produced are
       compressed using gzip.  Each `global' manual page  hierarchy  such  as  /usr/share/man  or
       /usr/X11R6/man  may  have  any directory as its cat page hierarchy.  Traditionally the cat
       pages are stored under the same hierarchy as the man pages, but for reasons such as  those
       specified  in the File Hierarchy Standard (FHS), it may be better to store them elsewhere.
       For details on how to do this, please read manpath(5).  For details on  why  to  do  this,
       read the standard.

       International  support  is  available with this package.  Native language manual pages are
       accessible (if available on your system) via use of locale functions.   To  activate  such
       support,  it  is  necessary  to set either $LC_MESSAGES, $LANG or another system dependent
       environment variable to your language locale, usually specified in the POSIX 1003.1  based
       format:

       <language>[_<territory>[.<character-set>[,<version>]]]

       If  the  desired  page  is  available  in your locale, it will be displayed in lieu of the
       standard (usually American English) page.

       Support for international message catalogues is also featured in this package and  can  be
       activated  in  the  same  way,  again if available.  If you find that the manual pages and
       message catalogues supplied with this package are not available in  your  native  language
       and  you would like to supply them, please contact the maintainer who will be coordinating
       such activity.

       For information regarding other features and extensions available with this manual  pager,
       please read the documents supplied with the package.

DEFAULTS

       man  will  search for the desired manual pages within the index database caches. If the -u
       option is given, a cache consistency check is performed to ensure the databases accurately
       reflect  the filesystem.  If this option is always given, it is not generally necessary to
       run mandb after the  caches  are  initially  created,  unless  a  cache  becomes  corrupt.
       However,  the  cache  consistency  check  can  be  slow  on systems with many manual pages
       installed, so it is not performed by default, and system administrators may  wish  to  run
       mandb every week or so to keep the database caches fresh.  To forestall problems caused by
       outdated caches, man will fall back to file globbing if a cache lookup fails, just  as  it
       would if no cache was present.

       Once  a  manual  page  has  been  located,  a check is performed to find out if a relative
       preformatted `cat' file already exists and is newer than the nroff file.  If it  does  and
       is,  this  preformatted  file  is  (usually) decompressed and then displayed, via use of a
       pager.  The pager can be specified in a number of ways,  or  else  will  fall  back  to  a
       default  is  used  (see  option  -P for details).  If no cat is found or is older than the
       nroff file, the nroff is filtered through various programs and is shown immediately.

       If a cat file can be produced  (a  relative  cat  directory  exists  and  has  appropriate
       permissions), man will compress and store the cat file in the background.

       The  filters  are deciphered by a number of means.  Firstly, the command line option -p or
       the environment variable $MANROFFSEQ  is  interrogated.   If  -p  was  not  used  and  the
       environment  variable  was  not  set,  the  initial line of the nroff file is parsed for a
       preprocessor string.  To contain a valid preprocessor string, the first line must resemble

       '\" <string>

       where string can be any combination of letters described by option -p below.

       If none of the above methods provide any filter information, a default set is used.

       A formatting pipeline is formed from the filters  and  the  primary  formatter  (nroff  or
       [tg]roff  with  -t)  and executed.  Alternatively, if an executable program mandb_nfmt (or
       mandb_tfmt with -t) exists in the man tree root, it is executed instead.  It  gets  passed
       the  manual source file, the preprocessor string, and optionally the device specified with
       -T or -E as arguments.

OPTIONS

       Non argument options that are duplicated either on the command line, in $MANOPT, or  both,
       are not harmful.  For options that require an argument, each duplication will override the
       previous argument value.

   General options
       -C file, --config-file=file
              Use this user configuration file rather than the default of ~/.manpath.

       -d, --debug
              Print debugging information.

       -D, --default
              This option is normally issued as the very first option and resets man's  behaviour
              to  its  default.   Its  use  is  to  reset those options that may have been set in
              $MANOPT.  Any options that follow -D will have their usual effect.

       --warnings[=warnings]
              Enable warnings from groff.  This may be used  to  perform  sanity  checks  on  the
              source  text of manual pages.  warnings is a comma-separated list of warning names;
              if it is not supplied, the default is "mac".  See the “Warnings” node in info groff
              for a list of available warning names.

   Main modes of operation
       -f, --whatis
              Equivalent  to  whatis.   Display  a  short  description  from  the manual page, if
              available.  See whatis(1) for details.

       -k, --apropos
              Equivalent to apropos.  Search the short manual page descriptions for keywords  and
              display any matches.  See apropos(1) for details.

       -K, --global-apropos
              Search  for  text in all manual pages.  This is a brute-force search, and is likely
              to take some time; if you can, you should specify a section to reduce the number of
              pages  that need to be searched.  Search terms may be simple strings (the default),
              or regular expressions if the --regex option is used.

              Note that this searches the sources of the manual pages, not the rendered text, and
              so  may  include  false  positives  due  to  things  like comments in source files.
              Searching the rendered text would be much slower.

       -l, --local-file
              Activate `local' mode.  Format and display local manual files instead of  searching
              through  the  system's  manual  collection.   Each  manual  page  argument  will be
              interpreted as an nroff source  file  in  the  correct  format.   No  cat  file  is
              produced.   If  '-'  is  listed  as  one of the arguments, input will be taken from
              stdin.  When this option is not used, and man fails  to  find  the  page  required,
              before  displaying  the  error  message,  it  attempts to act as if this option was
              supplied, using the name as a filename and looking for an exact match.

       -w, --where, --path, --location
              Don't actually display the manual pages, but do print the location(s) of the source
              nroff files that would be formatted.

       -W, --where-cat, --location-cat
              Don't  actually  display  the manual pages, but do print the location(s) of the cat
              files that would be displayed.  If  -w  and  -W  are  both  specified,  print  both
              separated by a space.

       -c, --catman
              This option is not for general use and should only be used by the catman program.

       -R encoding, --recode=encoding
              Instead of formatting the manual page in the usual way, output its source converted
              to the specified encoding.  If you already know the encoding of  the  source  file,
              you  can  also use manconv(1) directly.  However, this option allows you to convert
              several manual pages to a single encoding without having to  explicitly  state  the
              encoding  of each, provided that they were already installed in a structure similar
              to a manual page hierarchy.

   Finding manual pages
       -L locale, --locale=locale
              man will normally determine your current  locale  by  a  call  to  the  C  function
              setlocale(3)  which  interrogates various environment variables, possibly including
              $LC_MESSAGES and $LANG.  To temporarily override the  determined  value,  use  this
              option  to  supply  a  locale  string  directly to man.  Note that it will not take
              effect until the search for pages actually begins.  Output such as the help message
              will always be displayed in the initially determined locale.

       -m system[,...], --systems=system[,...]
              If  this  system  has  access to other operating system's manual pages, they can be
              accessed using this option.  To search for a manual page from NewOS's  manual  page
              collection, use the option -m NewOS.

              The  system  specified  can  be  a  combination of comma delimited operating system
              names.  To include a search of the native operating system's manual pages,  include
              the  system name man in the argument string.  This option will override the $SYSTEM
              environment variable.

       -M path, --manpath=path
              Specify an alternate manpath to use.  By default, man uses manpath derived code  to
              determine  the  path  to  search.   This  option overrides the $MANPATH environment
              variable and causes option -m to be ignored.

              A path specified as a  manpath  must  be  the  root  of  a  manual  page  hierarchy
              structured  into sections as described in the man-db manual (under "The manual page
              system").  To view manual pages outside such hierarchies, see the -l option.

       -S list, -s list, --sections=list
              List is a colon- or comma-separated list of `order  specific'  manual  sections  to
              search.  This option overrides the $MANSECT environment variable.  (The -s spelling
              is for compatibility with System V.)

       -e sub-extension, --extension=sub-extension
              Some systems incorporate large  packages  of  manual  pages,  such  as  those  that
              accompany  the Tcl package, into the main manual page hierarchy.  To get around the
              problem of having two manual pages with the same name  such  as  exit(3),  the  Tcl
              pages  were  usually  all assigned to section l.  As this is unfortunate, it is now
              possible to put the pages  in  the  correct  section,  and  to  assign  a  specific
              `extension'  to  them,  in this case, exit(3tcl).  Under normal operation, man will
              display exit(3) in preference to exit(3tcl).  To negotiate this  situation  and  to
              avoid  having  to  know  which  section  the page you require resides in, it is now
              possible to give man a sub-extension string indicating which package the page  must
              belong  to.   Using  the  above  example,  supplying  the option -e tcl to man will
              restrict the search to pages having an extension of *tcl.

       -i, --ignore-case
              Ignore case when searching for manual pages.  This is the default.

       -I, --match-case
              Search for manual pages case-sensitively.

       --regex
              Show all pages with any part of either their names or their  descriptions  matching
              each  page  argument  as  a regular expression, as with apropos(1).  Since there is
              usually no reasonable way to pick a  "best"  page  when  searching  for  a  regular
              expression, this option implies -a.

       --wildcard
              Show  all  pages with any part of either their names or their descriptions matching
              each page argument using shell-style wildcards, as with apropos(1) --wildcard.  The
              page  argument  must  match  the  entire  name  or  description,  or  match on word
              boundaries in the description.  Since there is usually no reasonable way to pick  a
              "best" page when searching for a wildcard, this option implies -a.

       --names-only
              If  the  --regex  or  --wildcard  option  is  used, match only page names, not page
              descriptions, as with whatis(1).  Otherwise, no effect.

       -a, --all
              By default, man will exit after displaying the most suitable manual page it  finds.
              Using  this option forces man to display all the manual pages with names that match
              the search criteria.

       -u, --update
              This option causes man to  perform  an  `inode  level'  consistency  check  on  its
              database  caches  to  ensure  that  they  are  an  accurate  representation  of the
              filesystem.  It will only have a useful effect if man is installed with the  setuid
              bit set.

       --no-subpages
              By  default,  man  will  try  to  interpret pairs of manual page names given on the
              command line as equivalent to a single manual page name containing a hyphen  or  an
              underscore.   This  supports the common pattern of programs that implement a number
              of subcommands, allowing them to provide manual pages for each that can be accessed
              using  similar  syntax  as would be used to invoke the subcommands themselves.  For
              example:

                $ man -aw git diff
                /usr/share/man/man1/git-diff.1.gz

              To disable this behaviour, use the --no-subpages option.

                $ man -aw --no-subpages git diff
                /usr/share/man/man1/git.1.gz
                /usr/share/man/man3/Git.3pm.gz
                /usr/share/man/man1/diff.1.gz

   Controlling formatted output
       -P pager, --pager=pager
              Specify which output pager to use.  By default, man uses pager, falling back to cat
              if  pager  is  not found or is not executable.  This option overrides the $MANPAGER
              environment variable, which in turn overrides the $PAGER environment variable.   It
              is not used in conjunction with -f or -k.

              The  value  may  be  a simple command name or a command with arguments, and may use
              shell quoting (backslashes, single quotes, or double quotes).  It may not use pipes
              to  connect  multiple  commands;  if you need that, use a wrapper script, which may
              take the file to display either as an argument or on standard input.

       -r prompt, --prompt=prompt
              If a recent version of less is used as the pager,  man  will  attempt  to  set  its
              prompt and some sensible options.  The default prompt looks like

               Manual page name(sec) line x

              where name denotes the manual page name, sec denotes the section it was found under
              and x the current line number.  This is achieved by  using  the  $LESS  environment
              variable.

              Supplying  -r with a string will override this default.  The string may contain the
              text $MAN_PN which will be expanded to the name of the current manual page and  its
              section  name  surrounded  by  `(' and `)'.  The string used to produce the default
              could be expressed as

              \ Manual\ page\ \$MAN_PN\ ?ltline\ %lt?L/%L.:
              byte\ %bB?s/%s..?\ (END):?pB\ %pB\\%..
              (press h for help or q to quit)

              It is broken into three lines here for the  sake  of  readability  only.   For  its
              meaning  see  the less(1) manual page.  The prompt string is first evaluated by the
              shell.  All double quotes, back-quotes  and  backslashes  in  the  prompt  must  be
              escaped  by a preceding backslash.  The prompt string may end in an escaped $ which
              may be followed by further options for less.  By default man sets the -ix8 options.

              The $MANLESS environment variable described below may be  used  to  set  a  default
              prompt string if none is supplied on the command line.

       -7, --ascii
              When  viewing a pure ascii(7) manual page on a 7 bit terminal or terminal emulator,
              some  characters  may  not  display  correctly  when  using  the  latin1(7)  device
              description  with  GNU  nroff.   This  option  allows pure ascii manual pages to be
              displayed in ascii with the latin1 device.  It will not translate any latin1  text.
              The  following table shows the translations performed: some parts of it may only be
              displayed properly when using GNU nroff's latin1(7) device.

              Description           Octal   latin1   ascii
              ─────────────────────────────────────────────
              continuation hyphen    255      ‐        -
              bullet (middle dot)    267      •        o
              acute accent           264      ´        '
              multiplication sign    327      ×        x

              If the latin1 column displays correctly, your terminal may be  set  up  for  latin1
              characters  and  this option is not necessary.  If the latin1 and ascii columns are
              identical, you are reading this page using this option or man did not  format  this
              page  using  the  latin1  device  description.   If the latin1 column is missing or
              corrupt, you may need to view manual pages with this option.

              This option is ignored when using options -t, -H, -T, or -Z and may be useless  for
              nroff other than GNU's.

       -E encoding, --encoding=encoding
              Generate  output  for  a  character  encoding other than the default.  For backward
              compatibility, encoding may be an nroff device such as ascii, latin1,  or  utf8  as
              well as a true character encoding such as UTF-8.

       --no-hyphenation, --nh
              Normally, nroff will automatically hyphenate text at line breaks even in words that
              do not contain hyphens, if it is necessary to do so to lay  out  words  on  a  line
              without  excessive  spacing.   This option disables automatic hyphenation, so words
              will only be hyphenated if they already contain hyphens.

              If you are writing a manual page and simply want to prevent nroff from  hyphenating
              a  word  at  an  inappropriate point, do not use this option, but consult the nroff
              documentation instead; for instance, you can put "\%" inside  a  word  to  indicate
              that  it  may  be  hyphenated  at that point, or put "\%" at the start of a word to
              prevent it from being hyphenated.

       --no-justification, --nj
              Normally, nroff will automatically justify  text  to  both  margins.   This  option
              disables  full  justification, leaving justified only to the left margin, sometimes
              called "ragged-right" text.

              If you are writing a manual page and simply want to prevent nroff  from  justifying
              certain  paragraphs,  do  not  use this option, but consult the nroff documentation
              instead; for instance, you can use the ".na", ".nf", ".fi", and ".ad"  requests  to
              temporarily disable adjusting and filling.

       -p string, --preprocessor=string
              Specify  the sequence of preprocessors to run before nroff or troff/groff.  Not all
              installations will have a full set of preprocessors.  Some of the preprocessors and
              the letters used to designate them are: eqn (e), grap (g), pic (p), tbl (t), vgrind
              (v), refer (r).   This  option  overrides  the  $MANROFFSEQ  environment  variable.
              zsoelim is always run as the very first preprocessor.

       -t, --troff
              Use groff -mandoc to format the manual page to stdout.  This option is not required
              in conjunction with -H, -T, or -Z.

       -T[device], --troff-device[=device]
              This option is used to change groff (or possibly troff's) output to be suitable for
              a  device  other  than  the  default.   It  implies  -t.   Examples  (provided with
              Groff-1.17) include dvi, latin1, ps, utf8, X75 and X100.

       -H[browser], --html[=browser]
              This option will cause groff to produce HTML output, and will display  that  output
              in  a  web  browser.   The  choice of browser is determined by the optional browser
              argument if one is provided, by the $BROWSER environment variable, or by a compile-
              time  default  if  that  is unset (usually lynx).  This option implies -t, and will
              only work with GNU troff.

       -X[dpi], --gxditview[=dpi]
              This option displays the output of groff in a graphical window using the  gxditview
              program.   The  dpi (dots per inch) may be 75, 75-12, 100, or 100-12, defaulting to
              75; the -12 variants use a 12-point base font.  This option  implies  -T  with  the
              X75, X75-12, X100, or X100-12 device respectively.

       -Z, --ditroff
              groff  will  run troff and then use an appropriate post-processor to produce output
              suitable for the chosen device.  If groff -mandoc is groff, this option  is  passed
              to groff and will suppress the use of a post-processor.  It implies -t.

   Getting help
       -?, --help
              Print a help message and exit.

       --usage
              Print a short usage message and exit.

       -V, --version
              Display version information.

EXIT STATUS

       0      Successful program execution.

       1      Usage, syntax or configuration file error.

       2      Operational error.

       3      A child process returned a non-zero exit status.

       16     At least one of the pages/files/keywords didn't exist or wasn't matched.

ENVIRONMENT

       MANPATH
              If $MANPATH is set, its value is used as the path to search for manual pages.

       MANROFFOPT
              The  contents  of  $MANROFFOPT are added to the command line every time man invokes
              the formatter (nroff, troff, or groff).

       MANROFFSEQ
              If $MANROFFSEQ is set, its value is used to determine the set of  preprocessors  to
              pass each manual page through.  The default preprocessor list is system dependent.

       MANSECT
              If  $MANSECT is set, its value is a colon-delimited list of sections and it is used
              to determine which manual sections to search and in what order.  The default is  "1
              n  l  8  3  2  3posix  3pm  3perl  3am 5 4 9 6 7", unless overridden by the SECTION
              directive in /etc/manpath.config.

       MANPAGER, PAGER
              If $MANPAGER or $PAGER is set ($MANPAGER is used in preference), its value is  used
              as  the  name of the program used to display the manual page.  By default, pager is
              used, falling back to cat if pager is not found or is not executable.

              The value may be a simple command name or a command with  arguments,  and  may  use
              shell quoting (backslashes, single quotes, or double quotes).  It may not use pipes
              to connect multiple commands; if you need that, use a  wrapper  script,  which  may
              take the file to display either as an argument or on standard input.

       MANLESS
              If  $MANLESS  is  set,  its value will be used as the default prompt string for the
              less pager, as if it had been passed using the -r option (so any occurrences of the
              text  $MAN_PN  will  be expanded in the same way).  For example, if you want to set
              the  prompt  string  unconditionally  to  “my  prompt  string”,  set  $MANLESS   to
              ‘-Psmy prompt string’.  Using the -r option overrides this environment variable.

       BROWSER
              If  $BROWSER is set, its value is a colon-delimited list of commands, each of which
              in turn is used to try to start a web browser for man --html.  In each command,  %s
              is  replaced by a filename containing the HTML output from groff, %% is replaced by
              a single percent sign (%), and %c is replaced by a colon (:).

       SYSTEM If $SYSTEM is set, it will have the same effect as if it had been specified as  the
              argument to the -m option.

       MANOPT If $MANOPT is set, it will be parsed prior to man's command line and is expected to
              be in a similar format.  As all of the other man specific environment variables can
              be expressed as command line options, and are thus candidates for being included in
              $MANOPT it is expected that they will  become  obsolete.   N.B.   All  spaces  that
              should be interpreted as part of an option's argument must be escaped.

       MANWIDTH
              If  $MANWIDTH  is  set, its value is used as the line length for which manual pages
              should be formatted.  If it is not set, manual pages will be formatted with a  line
              length  appropriate  to  the  current  terminal  (using  the  value of $COLUMNS, an
              ioctl(2) if available, or falling back to 80 characters if neither  is  available).
              Cat  pages will only be saved when the default formatting can be used, that is when
              the terminal line length is between 66 and 80 characters.

       MAN_KEEP_FORMATTING
              Normally, when output is not being directed to a terminal (such as to a file  or  a
              pipe),  formatting  characters  are  discarded to make it easier to read the result
              without special tools.  However, if $MAN_KEEP_FORMATTING is set  to  any  non-empty
              value,  these  formatting characters are retained.  This may be useful for wrappers
              around man that can interpret formatting characters.

       MAN_KEEP_STDERR
              Normally, when output is being directed to a terminal (usually  to  a  pager),  any
              error output from the command used to produce formatted versions of manual pages is
              discarded to avoid interfering with the pager's display.  Programs  such  as  groff
              often  produce relatively minor error messages about typographical problems such as
              poor alignment, which are unsightly and generally confusing  when  displayed  along
              with  the  manual  page.   However,  some  users  want  to  see them anyway, so, if
              $MAN_KEEP_STDERR is set to any non-empty value, error output will be  displayed  as
              usual.

       LANG, LC_MESSAGES
              Depending  on  system  and implementation, either or both of $LANG and $LC_MESSAGES
              will be interrogated for the current message locale.  man will display its messages
              in that locale (if available).  See setlocale(3) for precise details.

FILES

       /etc/manpath.config
              man-db configuration file.

       /usr/share/man
              A global manual page hierarchy.

       /usr/share/man/index.(bt|db|dir|pag)
              A traditional global index database cache.

       /var/cache/man/index.(bt|db|dir|pag)
              An FHS compliant global index database cache.

SEE ALSO

       apropos(1),  groff(1),  less(1),  manpath(1),  nroff(1),  troff(1), whatis(1), zsoelim(1),
       setlocale(3), manpath(5), ascii(7), latin1(7), man(7),  catman(8),  mandb(8),  the  man-db
       package manual, FSSTND

HISTORY

       1990, 1991 – Originally written by John W. Eaton (jwe@che.utexas.edu).

       Dec  23  1992:  Rik  Faith (faith@cs.unc.edu) applied bug fixes supplied by Willem Kasdorp
       (wkasdo@nikhefk.nikef.nl).

       30th  April  1994  –  23rd  February  2000:  Wilf.  (G.Wilford@ee.surrey.ac.uk)  has  been
       developing and maintaining this package with the help of a few dedicated people.

       30th October 1996 – 30th March 2001: Fabrizio Polacco <fpolacco@debian.org> maintained and
       enhanced this package for the Debian project, with the help of all the community.

       31st March 2001 – present day: Colin Watson <cjwatson@debian.org> is  now  developing  and
       maintaining man-db.