path: root/sem_5/HLIN505_Java/HLIN505/zbeb.txt

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-justification]  [-p
       string]   [-t]   [-T[device]]   [-H[browser]]   [-X[dpi]]  [-Z]  [[section]
       page ...] ...
       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  nor‐
       mally  the name of a program, utility or function.  The manual page associ‐
       ated 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 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, DESCRIP‐
       TION, OPTIONS, EXIT STATUS, RETURN VALUE, ERRORS, ENVIRONMENT, FILES,  VER‐
       SIONS, CONFORMING TO, NOTES, BUGS, EXAMPLE, AUTHORS, and SEE ALSO.

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


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

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

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

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

       man -a intro
           Display,  in  succession,  all of the available intro manual pages con‐
           tained 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 fur‐
           ther 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
       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 back‐
       slash).  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  man‐
       ual 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 informa‐
       tion 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 compres‐
       sion 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  man‐
       path(5).  For details on why to do this, read the standard.

       International support is available with this package.  Native language man‐
       ual 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 pack‐
       age  and can be activated in the same way, again if available.  If you find
       that the manual pages and message catalogues supplied with this package are
       not  available  in  your native language and you would like to supply them,
       please contact the maintainer who will be coordinating such activity.

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

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

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

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

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

       '\" <string>

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

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

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

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

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

       -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-sep‐
              arated list of warning names; if it is not supplied, the default  is
              "mac".   See  the “Warnings” node in info groff for a list of avail‐
              able 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 expres‐
              sions if the --regex option is used.

       -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  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 simi‐
              lar 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 vari‐
              ables, 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 operat‐
              ing  system names.  To include a search of the native operating sys‐
              tem'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 opera‐
              tion, 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 descrip‐
              tions 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 descrip‐
              tions 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 man‐
              ual 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 represen‐
              tation  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 pat‐
              tern  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 them‐
              selves.  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  -s.
              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 ter‐
              minal 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 dis‐
              played 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 hyphen‐
              ated 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 con‐
              sult  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 des‐
              ignate them are: eqn (e), grap (g), pic (p), tbl  (t),  vgrind  (v),
              refer  (r).  This option overrides the $MANROFFSEQ environment vari‐
              able.  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  dis‐
              play  that output in a web browser.  The choice of browser is deter‐
              mined by the optional browser argument if one is  provided,  by  the
              $BROWSER  environment variable, or by a compile-time default if that
              is unset (usually lynx).  This option implies -t, and will only work
              with GNU troff.

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

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

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

       --usage
              Print a short usage message and exit.

       -V, --version
              Display version information.

EXIT STATUS
       0      Successful program execution.

       1      Usage, syntax or configuration file error.

       2      Operational error.

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

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

ENVIRONMENT
       MANPATH
              If $MANPATH is set, its value is used as the path to search for man‐
              ual 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  pre‐
              processor list is system dependent.

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

       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 -s 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  environ‐
              ment 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 spe‐
              cific  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 ter‐
              minal  (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.

       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  dis‐
              played  along with the manual page.  However, some users want to see
              them anyway, so, if $MAN_KEEP_STDERR is set to any non-empty  value,
              error output will be displayed as usual.

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

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

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

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

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

SEE ALSO
       apropos(1), groff(1), less(1), manpath(1), nroff(1),  troff(1),  whatis(1),
       zsoelim(1),  setlocale(3),  manpath(5),  ascii(7),  latin1(7), man(7), cat‐
       man(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  dedi‐
       cated 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.



2.6.7.1                             2014-04-10                              MAN(1)