man(1)



MAN(1)                        Manual pager utils                        MAN(1)

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-justifi-
       cation]  [-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 termi-
       nal, 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 sev-
       eral 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  suc-
           cessive displays or skip any of them.

       man -t alias | lpr -Pps
           Format  the manual page referenced by `alias', usually a shell man-
           ual page, into the default troff or groff format and pipe it to the
           printer  named  ps.   The default output for groff is usually Post-
           Script.  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  redi-
           rection 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,  sec-
       tion  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 (pre-
       ceded 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  data-
       bases.

       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 com-
       pile 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  Hierar-
       chy  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 coordi-
       nating 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  per-
       formed  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 data-
       base  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  ini-
       tial  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  for-
       matter  (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  argu-
       ment, 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 man-
              ual page, if available.  See whatis(1) for details.

       -k, --apropos
              Equivalent to apropos.  Search the short  manual  page  descrip-
              tions  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 loca-
              tion(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  loca-
              tion(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 man-
              conv(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 hier-
              archy.

   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 tempo-
              rarily  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 oper-
              ating system's manual pages, include the system name man in  the
              argument string.  This option will override the $SYSTEM environ-
              ment variable.

       -M path, --manpath=path
              Specify an alternate manpath to use.  By default, man uses  man-
              path  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,  sup-
              plying  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  expres-
              sion,  as with apropos(1).  Since there is usually no reasonable
              way to pick a "best" page when searching for a  regular  expres-
              sion, 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 wild-
              cards,  as  with  apropos(1) --wildcard.  The page argument must
              match the entire name or description, or match  on  word  bound-
              aries  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 subcom-
              mands, 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.
              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 argu-
              ments, and may use shell quoting (backslashes, single quotes, or
              double  quotes).   It may not use pipes to connect multiple com-
              mands; 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 sur-
              rounded 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        o
              dot)
              acute accent      264      '        '
              multiplication    327      x        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 pre-
              processors.  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  environ-
              ment  variable.   zsoelim  is  always run as the very first pre-
              processor.

       -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 sup-
              press 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 sec-
              tions 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.

              The  value  may be a simple command name or a command with argu-
              ments, and may use shell quoting (backslashes, single quotes, or
              double  quotes).   It may not use pipes to connect multiple com-
              mands; 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 envi-
              ronment variable.

       BROWSER
              If  $BROWSER is set, its value is a colon-delimited list of com-
              mands, 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, man-
              ual 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 for-
              matting 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.  How-
              ever, 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  charac-
              ters.

       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 inter-
              fering 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  gener-
              ally  confusing when displayed along with the manual page.  How-
              ever,  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 avail-
              able).  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   <fpo-
       lacco@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.

2.7.6.1                           2016-12-12                            MAN(1)

Man(1) output converted with man2html
list of all man pages