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NAME    [Toc]    [Back]

       man - an interface to the on-line reference manuals

SYNOPSIS    [Toc]    [Back]

       man  [-c|-w|-tZHT  device]  [-adhu7V] [-m system[,...]] [-L locale] [-p
       string] [-M path] [-P pager]  [-r  prompt]  [-S	list]  [-e  extension]
       [[section] page ...] ...
       man  -l [-7] [-tZHT device] [-p string] [-P pager] [-r prompt] file ...
       man -k [apropos options] regexp ...
       man -f [whatis options] page ...

DESCRIPTION    [Toc]    [Back]

       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 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 system libraries)
       4   Special files (usually found in /dev)
       5   File formats and conventions eg /etc/passwd
       6   Games
       7   Macro packages and conventions eg man(7), groff(7).
       8   System administration commands (usually only for root)
       9   Kernel routines [Non standard]

       A manual page consists of several parts.

       They  may  be  labelled	NAME,  SYNOPSIS,  DESCRIPTION, OPTIONS, FILES,
       SEE ALSO, BUGS, and AUTHOR.

       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.

       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    [Toc]    [Back]

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

       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 -r printf.

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

OVERVIEW    [Toc]    [Back]

       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 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:


       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    [Toc]    [Back]

       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

       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 as arguments.

OPTIONS    [Toc]    [Back]

       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.

       -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.

       -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.

       -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.

       -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.

       -P pager, --pager=pager
	      Specify  which  output  pager to use.  By default, man uses exec
	      /usr/bin/pager -s.  This option overrides the $PAGER environment
	      variable and is not used in conjunction with -f or -k.

       -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\\%..

	      It  is  broken  into  two 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.

       -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.

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

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

       -S list, --sections=list
	      List  is	a colon-separated list of `order specific' manual sections
 to search.	This option overrides the $MANSECT environment

       -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.

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

       -d, --debug
	      Don't  actually  display	any manual pages, but do print lots of
	      debugging information.

       -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 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.

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

       -h, --help
	      Print a help message and exit.

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

       -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

       -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.

       -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.

       -t, --troff
	      Use /usr/bin/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-1.09) include dvi, latin1,
	      X75 and X100.

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

       -H, --html
	      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  $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.

       -w, --where, --location
	      Don't  actually display the manual pages, but do print the location(s)
 of the files that would be formatted or  displayed.   If
	      the  file  is  a	cat file, also show the location of its source
	      nroff file.

       -V, --version
	      Display version information.

EXIT STATUS    [Toc]    [Back]

       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

ENVIRONMENT    [Toc]    [Back]

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

       MANROFFSEQ    [Toc]    [Back]
	      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    [Toc]    [Back]
	      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.

       PAGER  If $PAGER is set, its value is used as the name of  the  program
	      used   to   display   the   manual   page.    By	default,  exec
	      /usr/bin/pager -s is used.

       BROWSER    [Toc]    [Back]
	      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 option -m
	      string where string will be taken as $SYSTEM's contents.

       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    [Toc]    [Back]
	      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 an ioctl(2) if available, the value
	      of $COLUMNS, 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.

	      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    [Toc]    [Back]

	      man_db configuration file.

	      A global manual page hierarchy.

	      A traditional global index database cache.

	      An alternate or FHS compliant global index database cache.

SEE ALSO    [Toc]    [Back]

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

HISTORY    [Toc]    [Back]

       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.sur-
       rey.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 - 07 September 2001: Colin Watson <cjwatson@debian.org>
       is now developing and maintaining man-db.

2.3.20			       07 September 2001			man(1)
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