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man(1)									man(1)



NAME
       man - format and display the on-line manual pages

SYNOPSIS
       man  [-acdfFhkKtwW]  [--path]  [-m system] [-p string] [-C config_file]
       [-M pathlist] [-P pager] [-B browser] [-H htmlpager] [-S	 section_list]
       [section] name ...


DESCRIPTION
       man formats and displays the on-line manual pages.  If you specify sec-
       tion, man only looks in that section of the manual.  name  is  normally
       the  name of the manual page, which is typically the name of a command,
       function, or file.  However, if name contains  a	 slash	(/)  then  man
       interprets  it  as a file specification, so that you can do man ./foo.5
       or even man /cd/foo/bar.1.gz.

       See below for a description of where man	 looks	for  the  manual  page
       files.


OPTIONS
       -C  config_file
	      Specify	the   configuration   file  to	use;  the  default  is
	      /etc/man.config.	(See man.config(5).)

       -M  path
	      Specify the list of directories to search for man pages.	 Sepa-
	      rate  the directories with colons.  An empty list is the same as
	      not specifying -M at all.	 See SEARCH PATH FOR MANUAL PAGES.

       -P  pager
	      Specify which pager to use.  This option overrides the  MANPAGER
	      environment  variable,  which  in turn overrides the PAGER vari-
	      able.  By default, man uses /usr/bin/less -is.

       -B     Specify which browser to use on HTML files.  This	 option	 over-
	      rides  the  BROWSER  environment	variable. By default, man uses
	      /usr/bin/less-is,

       -H     Specify a command that renders HTML files as text.  This	option
	      overrides	 the  HTMLPAGER	 environment variable. By default, man
	      uses /bin/cat,

       -S  section_list
	      List is a colon separated list of	 manual	 sections  to  search.
	      This option overrides the MANSECT environment variable.

       -a     By default, man will exit after displaying the first manual page
	      it finds.	 Using this option forces man to display all the  man-
	      ual pages that match name, not just the first.

       -c     Reformat	the  source man page, even when an up-to-date cat page
	      exists.  This can be meaningful if the cat  page	was  formatted
	      for  a screen with a different number of columns, or if the pre-
	      formatted page is corrupted.

       -d     Don't actually display the man  pages,  but  do  print  gobs  of
	      debugging information.

       -D     Both display and print debugging info.

       -f     Equivalent to whatis.

       -F or --preformat
	      Format only - do not display.

       -h     Print a help message and exit.

       -k     Equivalent to apropos.

       -K     Search  for  the	specified  string in *all* man pages. Warning:
	      this is probably very slow!  It  helps  to  specify  a  section.
	      (Just  to	 give  a  rough idea, on my machine this takes about a
	      minute per 500 man pages.)

       -m  system
	      Specify an alternate set of man pages to	search	based  on  the
	      system name given.

       -p  string
	      Specify  the  sequence  of  preprocessors to run before nroff or
	      troff.  Not all installations will have a full set of preproces-
	      sors.   Some of the preprocessors and the letters used to desig-
	      nate them are: eqn (e), grap (g), pic (p), tbl (t), vgrind  (v),
	      refer  (r).   This  option  overrides the MANROFFSEQ environment
	      variable.

       -t     Use /usr/bin/groff -Tps -mandoc to format the manual page, pass-
	      ing  the	output	to  stdout.   The  default  output  format  of
	      /usr/bin/groff -Tps -mandoc is Postscript, refer to  the	manual
	      page  of	/usr/bin/groff -Tps -mandoc for ways to pick an alter-
	      nate format.

       Depending on the selected  format  and  the  availability  of  printing
       devices,	 the  output  may  need	 to  be	 passed through some filter or
       another before being printed.

       -w or --path
	      Don't actually display the man pages, but	 do  print  the	 loca-
	      tion(s) of the files that would be formatted or displayed. If no
	      argument is given: display (on stdout) the list  of  directories
	      that  is	searched by man for man pages. If manpath is a link to
	      man, then "manpath" is equivalent to "man --path".

       -W     Like -w, but print file names one per line,  without  additional
	      information.   This is useful in shell commands like man -aW man
	      | xargs ls -l


CAT PAGES
       Man will try to save the formatted man pages, in order to save  format-
       ting time the next time these pages are needed.	Traditionally, format-
       ted versions of pages in DIR/manX are saved in DIR/catX, but other map-
       pings  from man dir to cat dir can be specified in /etc/man.config.  No
       cat pages are saved when the required cat directory does not exist.  No
       cat pages are saved when they are formatted for a line length different
       from 80.	 No cat pages are saved	 when  man.config  contains  the  line
       NOCACHE.

       It is possible to make man suid to a user man. Then, if a cat directory
       has owner man and mode 0755 (only writable by man), and the  cat	 files
       have  owner  man	 and  mode  0644 or 0444 (only writable by man, or not
       writable at all), no ordinary user can change  the  cat	pages  or  put
       other  files  in the cat directory. If man is not made suid, then a cat
       directory should have mode 0777 if all users should be  able  to	 leave
       cat pages there.

       The  option  -c	forces	reformatting a page, even if a recent cat page
       exists.


HTML PAGES
       Man will find HTML pages if they live in directories named as  expected
       to  be  ".html", thus a valid name for an HTML version of the ls(1) man
       page would be /usr/share/man/htmlman1/ls.1.html.


SEARCH PATH FOR MANUAL PAGES
       man uses a sophisticated method of finding manual page files, based  on
       the  invocation	options and environment variables, the /etc/man.config
       configuration file, and some built in conventions and heuristics.

       First of all, when the name argument to man contains a slash  (/),  man
       assumes	it  is	a file specification itself, and there is no searching
       involved.

       But in the normal case where name doesn't contain a slash, man searches
       a variety of directories for a file that could be a manual page for the
       topic named.

       If you specify the -M pathlist option, pathlist	is  a  colon-separated
       list of the directories that man searches.

       If  you	don't specify -M but set the MANPATH environment variable, the
       value of that  variable	is  the	 list  of  the	directories  that  man
       searches.

       If  you	don't  specify	an  explicit path list with -M or MANPATH, man
       develops its own path list based on the contents of  the	 configuration
       file /etc/man.config.  The MANPATH statements in the configuration file
       identify particular directories to include in the search path.

       Furthermore, the MANPATH_MAP statements add to the search path  depend-
       ing  on your command search path (i.e. your PATH environment variable).
       For each directory that may be in  the  command	search	path,  a  MAN-
       PATH_MAP	 statement  specifies  a directory that should be added to the
       search path for manual page files.  man looks at the PATH variable  and
       adds the corresponding directories to the manual page file search path.
       Thus, with the proper use of MANPATH_MAP, when you  issue  the  command
       man  xyz,  you  get a manual page for the program that would run if you
       issued the command xyz.

       In addition, for each directory in the command search path (we'll  call
       it  a  "command	directory")  for  which	 you do not have a MANPATH_MAP
       statement, man automatically looks for a manual page directory "nearby"
       namely as a subdirectory in the command directory itself or in the par-
       ent directory of the command directory.

       You can disable the automatic "nearby" searches by  including  a	 NOAU-
       TOPATH statement in /etc/man.config.

       In  each	 directory in the search path as described above, man searches
       for a file named topic.section, with an optional suffix on the  section
       number  and  possibly  a compression suffix.  If it doesn't find such a
       file, it then looks in any subdirectories named manN or catN where N is
       the  manual section number.  If the file is in a catN subdirectory, man
       assumes it is a formatted manual page file (cat page).  Otherwise,  man
       assumes it is unformatted.  In either case, if the filename has a known
       compression suffix (like .gz), man assumes it is gzipped.

       If you want to see where (or if) man would find the manual page	for  a
       particular topic, use the --path (-w) option.


ENVIRONMENT
       MANPATH
	      If  MANPATH is set, man uses it as the path to search for manual
	      page files.  It overrides the configuration file and  the	 auto-
	      matic  search  path,  but	 is  overridden	 by  the -M invocation
	      option.  See SEARCH PATH FOR MANUAL PAGES.

       MANPL  If MANPL is set, its value is used as the display	 page  length.
	      Otherwise, the entire man page will occupy one (long) page.

       MANROFFSEQ
	      If  MANROFFSEQ is set, its value is used to determine the set of
	      preprocessors run before running nroff or	 troff.	  By  default,
	      pages are passed through the tbl preprocessor before nroff.

       MANSECT
	      If  MANSECT  is set, its value is used to determine which manual
	      sections to search.

       MANWIDTH
	      If MANWIDTH is set, its value is	used  as  the  width  manpages
	      should  be displayed.  Otherwise the pages may be displayed over
	      the whole width of your screen.

       MANPAGER
	      If MANPAGER is set, its value is used as the name of the program
	      to  use to display the man page.	If not, then PAGER is used. If
	      that has no value either, /usr/bin/less -is is used.

       BROWSER
	      The name of a browser to use for displaying HTML	manual	pages.
	      If it is not set, /usr/bin/less -is is used.

       HTMLPAGER
	      The  command to use for rendering HTML manual pages as text.  If
	      it is not set, /bin/cat is used.

       LANG   If LANG is set, its value defines the name of  the  subdirectory
	      where  man first looks for man pages. Thus, the command 'LANG=dk
	      man 1 foo' will cause man to  look  for  the  foo	 man  page  in
	      .../dk/man1/foo.1,  and  if  it cannot find such a file, then in
	      .../man1/foo.1, where ... is a directory on the search path.

       NLSPATH, LC_MESSAGES, LANG
	      The environment variables NLSPATH and LC_MESSAGES (or LANG  when
	      the  latter  does not exist) play a role in locating the message
	      catalog.	(But the English messages are  compiled	 in,  and  for
	      English no catalog is required.)	Note that programs like col(1)
	      called by man also use e.g. LC_CTYPE.

       PATH   PATH helps determine the search path for manual page files.  See
	      SEARCH PATH FOR MANUAL PAGES.

       SYSTEM SYSTEM is used to get the default alternate system name (for use
	      with the -m option).

BUGS
       The -t option only works if a troff-like program is installed.
       If you see blinking  \255  or  <AD>  instead  of	 hyphens,  put	'LESS-
       CHARSET=latin1' in your environment.

TIPS
       If you add the line

	(global-set-key	  [(f1)]   (lambda   ()	  (interactive)	 (manual-entry
       (current-word))))

       to your .emacs file, then hitting F1 will give you the man page for the
       library call at the current cursor position.

       To  get	a  plain  text	version	 of a man page, without backspaces and
       underscores, try

	 # man foo | col -b > foo.mantxt

AUTHOR
       John W. Eaton was the  original	author	of  man.   Zeyd	 M.  Ben-Halim
       released	 man  1.2,  and	 Andries Brouwer followed up with versions 1.3
       thru 1.5p.  Federico  Lucifredi	<flucifredi@acm.org>  is  the  current
       maintainer.

SEE ALSO
       apropos(1), whatis(1), less(1), groff(1), man.config(5).



			      September 19, 2005			man(1)
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