NAME | SYNOPSIS | DESCRIPTION | EXAMPLES | OVERVIEW | DEFAULTS | OPTIONS | EXIT STATUS | ENVIRONMENT | FILES | SEE ALSO | HISTORY | COLOPHON

MAN(1)                       Manual pager utils                       MAN(1)

NAME         top

       man - an interface to the on-line reference manuals

SYNOPSIS         top

       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         top

       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 5 4 9
       6 7" by default, unless overridden by the SECTION directive in
       /usr/local/etc/man_db.conf), 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         top

       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         top

       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         top

       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         top

       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 less.
              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      255      ‐        -
              hyphen
              bullet (middle    267      ·        o
              dot)
              acute accent      264      ´        '
              multiplication    327      ×        x
              sign

              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         top

       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         top

       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 5 4 9 6
              7", unless overridden by the SECTION directive in
              /usr/local/etc/man_db.conf.

       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, less is used.

              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         top

       /usr/local/etc/man_db.conf
              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         top

       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         top

       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.

COLOPHON         top

       This page is part of the man-db (manual pager suite) project.
       Information about the project can be found at 
       ⟨http://www.nongnu.org/man-db/⟩.  If you have a bug report for this
       manual page, send it to man-db-devel@nongnu.org.  This page was
       obtained from the project's upstream Git repository 
       ⟨http://git.savannah.gnu.org/r/man-db.git⟩ on 2017-03-13.  If you dis‐
       cover any rendering problems in this HTML version of the page, or you
       believe there is a better or more up-to-date source for the page, or
       you have corrections or improvements to the information in this
       COLOPHON (which is not part of the original manual page), send a mail
       to man-pages@man7.org

2.7.6.1                          2016-12-12                           MAN(1)