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diff --git a/man/man1/man.man1 b/man/man1/man.man1 new file mode 100644 index 0000000..6319d5b --- /dev/null +++ b/man/man1/man.man1 @@ -0,0 +1,1303 @@ +'\" t +.\" ** The above line should force tbl to be a preprocessor ** +.\" Man page for man +.\" +.\" Copyright (C) 1994, 1995, Graeme W. Wilford. (Wilf.) +.\" Copyright (C) 2001-2019 Colin Watson. +.\" +.\" You may distribute under the terms of the GNU General Public +.\" License as specified in the file docs/COPYING.GPLv2 that comes with the +.\" man-db distribution. +.\" +.\" Sat Oct 29 13:09:31 GMT 1994 Wilf. (G.Wilford@ee.surrey.ac.uk) +.\" +.pc +.TH %thman% 1 "%date%" "%version%" "Manual pager utils" +.SH NAME +%man% \- an interface to the system reference manuals +.SH SYNOPSIS +.\" The general command line +.B %man% +.RI [\| "man options" \|] +.RI [\|[\| section \|] +.IR page \ \|.\|.\|.\|]\ \.\|.\|.\& +.\" The apropos command line +.br +.B %man% +.B \-k +.RI [\| "apropos options" \|] +.I regexp +\&.\|.\|.\& +.\" The --global-apropos command line +.br +.B %man% +.B \-K +.RI [\| "man options" \|] +.RI [\| section \|] +.IR term \ .\|.\|.\& +.\" The whatis command line +.br +.B %man% +.B \-f +.RI [\| whatis +.IR options \|] +.I page +\&.\|.\|.\& +.\" The --local command line +.br +.B %man% +.B \-l +.RI [\| "man options" \|] +.I file +\&.\|.\|.\& +.\" The --where/--where-cat command line +.br +.B %man% +.BR \-w \||\| \-W +.RI [\| "man options" \|] +.I page +\&.\|.\|.\& +.SH DESCRIPTION +.B %man% +is the system's manual pager. +Each +.I page +argument given to +.B %man% +is normally the name of a program, utility or function. +The +.I manual page +associated with each of these arguments is then found and displayed. +A +.IR section , +if provided, will direct +.B %man% +to look only in that +.I section +of the manual. +The default action is to search in all of the available +.I sections +following a pre-defined order (see +.BR DEFAULTS ), +and to show only the first +.I page +found, even if +.I page +exists in several +.IR sections . + +The table below shows the +.I section +numbers of the manual followed by the types of pages they contain. + +.TS +tab (@); +l lx. +1@T{ +Executable programs or shell commands +T} +2@T{ +System calls (functions provided by the kernel) +T} +3@T{ +Library calls (functions within program libraries) +T} +4@T{ +Special files (usually found in \fI/dev\/\fR) +T} +5@T{ +File formats and conventions, e.g.\& \fI/etc/passwd\fR +T} +6@T{ +Games +T} +7@T{ +Miscellaneous (including macro packages and conventions), +e.g.\& \fBman\fR(7), \fBgroff\fR(7), \fBman\-pages\fR(7) +T} +8@T{ +System administration commands (usually only for root) +T} +9@T{ +Kernel routines [\|Non standard\|] +T} +.TE + +A manual +.I page +consists of several sections. + +Conventional section names include +.BR NAME , +.BR SYNOPSIS , +.BR CONFIGURATION , +.BR DESCRIPTION , +.BR OPTIONS , +.BR EXIT\ STATUS , +.BR RETURN\ VALUE , +.BR ERRORS , +.BR ENVIRONMENT , +.BR FILES , +.BR VERSIONS , +.BR CONFORMING\ TO , +.BR NOTES , +.BR BUGS , +.BR EXAMPLE , +.BR AUTHORS , +and +.BR SEE\ ALSO . + +The following conventions apply to the +.B SYNOPSIS +section and can be used as a guide in other sections. + +.TS +tab (@); +l lx. +\fBbold text\fR@T{ +type exactly as shown. +T} +\fIitalic text\fR@T{ +replace with appropriate argument. +T} +[\|\fB\-abc\fR\|]@T{ +any or all arguments within [ ] are optional. +T} +\fB\-a\|\fR|\|\fB\-b\fR@T{ +options delimited by | cannot be used together. +T} +\fIargument\fR .\|.\|.@T{ +\fIargument\fR is repeatable. +T} +[\|\fIexpression\fR\|]\fR .\|.\|.@T{ +\fRentire \fIexpression\fR\ within [ ] is repeatable. +T} +.TE + +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 +.B SYNOPSIS +section of this manual page. +.SH EXAMPLES +.TP \w'%man%\ 'u +.BI %man% \ ls +Display the manual page for the +.I item +(program) +.IR ls . +.TP +\fB%man%\fR \fIman\fR.\fI7\fR +Display the manual page for macro package +.I man +from section +.IR 7 . +(This is an alternative spelling of +"\fB%man%\fR \fI7 man\fR".) +.TP +\fB%man% '\fIman\fR(\fI7\fR)' +Display the manual page for macro package +.I man +from section +.IR 7 . +(This is another alternative spelling of +"\fB%man%\fR \fI7 man\fR". +It may be more convenient when copying and pasting cross-references to +manual pages. +Note that the parentheses must normally be quoted to protect them from the +shell.) +.TP +.BI %man%\ \-a \ intro +Display, in succession, all of the available +.I intro +manual pages contained within the manual. +It is possible to quit between successive displays or skip any of them. +.TP +\fB%man% \-t \fIbash \fR|\fI lpr \-Pps +Format the manual page for +.I bash +into the default +.B troff +or +.B groff +format and pipe it to the printer named +.IR ps . +The default output for +.B groff +is usually PostScript. +.B %man% \-\-help +should advise as to which processor is bound to the +.B \-t +option. +.TP +.BI "%man% \-l \-T" "dvi ./foo.1x.gz" " > " ./foo.1x.dvi +This command will decompress and format the nroff source manual page +.I ./foo.1x.gz +into a +.B device independent (dvi) +file. +The redirection is necessary as the +.B \-T +flag causes output to be directed to +.B stdout +with no pager. +The output could be viewed with a program such as +.B xdvi +or further processed into PostScript using a program such as +.BR dvips . +.TP +.BI %man%\ \-k \ printf +Search the short descriptions and manual page names for the keyword +.I printf +as regular expression. +Print out any matches. +Equivalent to +.BI %apropos% \ printf . +.TP +.BI %man%\ \-f \ smail +Lookup the manual pages referenced by +.I smail +and print out the short descriptions of any found. +Equivalent to +.BI %whatis% \ smail . +.SH OVERVIEW +Many options are available to +.B %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 +.BR %man% . +It is possible to set the "catch-all" variable +.RB $ 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). +.B %man% +will parse +.RB $ 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 +.RB $ MANOPT , +.B \-D +can be specified as the initial command line option. +This will allow %man% to "forget" about the options specified in +.RB $ MANOPT , +although they must still have been valid. + +Manual pages are normally stored in +.BR nroff (1) +format under a directory such as +.IR /usr/share/man . +In some installations, there may also be preformatted +.I cat pages +to improve performance. +See +.BR manpath (5) +for details of where these files are stored. + +This package supports manual pages in multiple languages, controlled by your +.IR locale . +If your system did not set this up for you automatically, then you may need +to set +.RB $ LC_MESSAGES , +.RB $ LANG , +or another system-dependent environment variable to indicate your preferred +locale, usually specified in the +.B POSIX +format: + +<\fIlanguage\fR>\ +[\|\fB_\fR<\fIterritory\fR>\|\ +[\|\fB.\fR<\fIcharacter-set\fR>\|\ +[\|\fB,\fR<\fIversion\fR>\|]\|]\|] + +If the desired page is available in your +.IR locale , +it will be displayed in lieu of the standard +(usually American English) page. + +If you find that the translations 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. + +Individual manual pages are normally written and maintained by the +maintainers of the program, function, or other topic that they document, and +are not included with this package. +If you find that a manual page is missing or inadequate, please report that +to the maintainers of the package in question. + +For information regarding other features and extensions available with this +manual pager, please read the documents supplied with the package. +.SH DEFAULTS +The order of sections to search may be overridden by the environment +variable +.RB $ MANSECT +or by the +.B SECTION +directive in +.IR %manpath_config_file% . +By default it is as follows: + +.RS +.if !'po4a'hide' %sections% +.RE + +The formatted manual page is displayed using a +.IR pager . +This can be specified in a number of ways, or else will fall back to a +default (see option +.B \-P +for details). + +The filters are deciphered by a number of means. +Firstly, the command line option +.B \-p +or the environment variable +.RB $ MANROFFSEQ +is interrogated. +If +.B \-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 + +.B '\e" +.RB < string > + +where +.B string +can be any combination of letters described by option +.B \-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 +.RB ( nroff +or +.RB [ tg ] roff +with +.BR \-t ) +and executed. +Alternatively, if an executable program +.I mandb_nfmt +(or +.I mandb_tfmt +with +.BR \-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 +.BR \-T " or " \-E +as arguments. +.\" ******************************************************************** +.SH OPTIONS +Non-argument options that are duplicated either on the command line, in +.RB $ MANOPT , +or both, are not harmful. +For options that require an argument, each duplication will override the +previous argument value. +.SS "General options" +.TP +.BI \-C\ file \fR,\ \fB\-\-config\-file= file +Use this user configuration file rather than the default of +.IR ~/.manpath . +.TP +.if !'po4a'hide' .BR \-d ", " \-\-debug +Print debugging information. +.TP +.if !'po4a'hide' .BR \-D ", " \-\-default +This option is normally issued as the very first option and resets +.B %man%'s +behaviour to its default. +Its use is to reset those options that may have been set in +.RB $ MANOPT . +Any options that follow +.B \-D +will have their usual effect. +.TP +\fB\-\-warnings\fP[=\fIwarnings\/\fP] +Enable warnings from +.IR groff . +This may be used to perform sanity checks on the source text of manual +pages. +.I warnings +is a comma-separated list of warning names; if it is not supplied, the +default is "mac". +See the \(lqWarnings\(rq node in +.B info groff +for a list of available warning names. +.SS "Main modes of operation" +.TP +.if !'po4a'hide' .BR \-f ", " \-\-whatis +Equivalent to +.BR %whatis% . +Display a short description from the manual page, if available. +See +.BR %whatis% (1) +for details. +.TP +.if !'po4a'hide' .BR \-k ", " \-\-apropos +Equivalent to +.BR %apropos% . +Search the short manual page descriptions for keywords and display any +matches. +See +.BR %apropos% (1) +for details. +.TP +.if !'po4a'hide' .BR \-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 +.B \-\-regex +option is used. +.IP +Note that this searches the +.I 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. +.TP +.if !'po4a'hide' .BR \-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. +.\" Compressed nroff source files with a supported compression +.\" extension will be decompressed by man prior to being displaying via the +.\" usual filters. +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. +.TP +.if !'po4a'hide' .BR \-w ", " \-\-where ", " \-\-path ", " \-\-location +Don't actually display the manual page, but do print the location of the +source nroff file that would be formatted. +If the +.B \-a +option is also used, then print the locations of all source files that match +the search criteria. +.TP +.if !'po4a'hide' .BR \-W ", " \-\-where\-cat ", " \-\-location\-cat +Don't actually display the manual page, but do print the location of the +preformatted cat file that would be displayed. +If the +.B \-a +option is also used, then print the locations of all preformatted cat files +that match the search criteria. +.IP +If +.B \-w +and +.B \-W +are both used, then print both source file and cat file separated by a +space. +If +all of +.BR \-w , +.BR \-W , +and +.B \-a +are used, then do this for each possible match. +.TP +.if !'po4a'hide' .BR \-c ", " \-\-catman +This option is not for general use and should only be used by the +.B %catman% +program. +.TP +.BI \-R\ encoding\fR,\ \fI \-\-recode\fR=\fIencoding +Instead of formatting the manual page in the usual way, output its source +converted to the specified +.IR encoding . +If you already know the encoding of the source file, you can also use +.BR %manconv% (1) +directly. +However, this option allows you to convert several manual pages to a single +encoding without having to explicitly state the encoding of each, provided +that they were already installed in a structure similar to a manual page +hierarchy. +.IP +Consider using +.BR %man_recode% (1) +instead for converting multiple manual pages, since it has an interface +designed for bulk conversion and so can be much faster. +.SS "Finding manual pages" +.TP +.BI \-L\ locale \fR,\ \fB\-\-locale= locale +.B %program% +will normally determine your current locale by a call to the C function +.BR setlocale (3) +which interrogates various environment variables, possibly including +.RB $ LC_MESSAGES +and +.RB $ LANG . +To temporarily override the determined value, use this option to supply a +.I locale +string directly to +.BR %program% . +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. +.TP +\fB\-m\fR \fIsystem\fR\|[\|,.\|.\|.\|]\|, \ +\fB\-\-systems=\fIsystem\fR\|[\|,.\|.\|.\|] +If this system has access to other operating systems' manual pages, they can +be accessed using this option. +To search for a manual page from NewOS's manual page collection, +use the option +.B \-m +.BR NewOS . + +The +.I 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 +.B man +in the argument string. +This option will override the +.RB $ SYSTEM +environment variable. +.TP +.BI \-M\ path \fR,\ \fB\-\-manpath= path +Specify an alternate manpath to use. +By default, +.B %man% +uses +.B %manpath% +derived code to determine the path to search. +This option overrides the +.RB $ MANPATH +environment variable and causes option +.B \-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 +.B \-l +option. +.TP +\fB\-S\fR \fIlist\/\fR, \ +\fB\-s\fR \fIlist\/\fR, \ +\fB\-\-sections=\fIlist\/\fR +The given +.I list +is a colon- or comma-separated list of sections, used to determine which +manual sections to search and in what order. +This option overrides the +.RB $ MANSECT +environment variable. +(The +.B \-s +spelling is for compatibility with System V.) +.TP +.BI \-e\ sub-extension \fR,\ \fB\-\-extension= sub-extension +Some systems incorporate large packages of manual pages, such as those that +accompany the +.B Tcl +package, into the main manual page hierarchy. +To get around the problem of having two manual pages with the same name +such as +.BR exit (3), +the +.B Tcl +pages were usually all assigned to section +.BR 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, +.BR exit (3tcl). +Under normal operation, +.B %man% +will display +.BR exit (3) +in preference to +.BR 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 +.B %man% +a +.I sub-extension +string indicating which package the page must belong to. +Using the above example, supplying the option +.B \-e\ tcl +to +.B %man% +will restrict the search to pages having an extension of +.BR *tcl . +.TP +.if !'po4a'hide' .BR \-i ", " \-\-ignore\-case +Ignore case when searching for manual pages. +This is the default. +.TP +.if !'po4a'hide' .BR \-I ", " \-\-match\-case +Search for manual pages case-sensitively. +.TP +.if !'po4a'hide' .B \-\-regex +Show all pages with any part of either their names or their descriptions +matching each +.I page +argument as a regular expression, as with +.BR apropos (1). +Since there is usually no reasonable way to pick a "best" page when +searching for a regular expression, this option implies +.BR \-a . +.TP +.if !'po4a'hide' .B \-\-wildcard +Show all pages with any part of either their names or their descriptions +matching each +.I page +argument using shell-style wildcards, as with +.BR apropos (1) +.BR \-\-wildcard . +The +.I 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 +.BR \-a . +.TP +.if !'po4a'hide' .B \-\-names\-only +If the +.B \-\-regex +or +.B \-\-wildcard +option is used, match only page names, not page descriptions, as with +.BR whatis (1). +Otherwise, no effect. +.TP +.if !'po4a'hide' .BR \-a ", " \-\-all +By default, +.B %man% +will exit after displaying the most suitable manual page it finds. +Using this option forces +.B %man% +to display all the manual pages with names that match the search criteria. +.TP +.if !'po4a'hide' .BR \-u ", " \-\-update +This option causes +.B %man% +to update its database caches of installed manual pages. +This is only needed in rare situations, and it is normally better to run +.BR %mandb% (8) +instead. +.TP +.if !'po4a'hide' .B \-\-no\-subpages +By default, +.B %man% +will try to interpret pairs of manual page names given on the command line +as equivalent to a single manual page name containing a hyphen or an +underscore. +This supports the common pattern of programs that implement a number of +subcommands, allowing them to provide manual pages for each that can be +accessed using similar syntax as would be used to invoke the subcommands +themselves. +For example: + +.nf +.if !'po4a'hide' \& $ man \-aw git diff +.if !'po4a'hide' \& /usr/share/man/man1/git\-diff.1.gz +.fi + +To disable this behaviour, use the +.B \-\-no\-subpages +option. + +.nf +.if !'po4a'hide' \& $ man \-aw \-\-no\-subpages git diff +.if !'po4a'hide' \& /usr/share/man/man1/git.1.gz +.if !'po4a'hide' \& /usr/share/man/man3/Git.3pm.gz +.if !'po4a'hide' \& /usr/share/man/man1/diff.1.gz +.fi +.SS "Controlling formatted output" +.TP +.BI \-P\ pager \fR,\ \fB\-\-pager= pager +Specify which output pager to use. +By default, +.B %man% +uses +.BR "%pager%" , +falling back to +.B %cat% +if +.B %pager% +is not found or is not executable. +This option overrides the +.RB $ MANPAGER +environment variable, which in turn overrides the +.RB $ PAGER +environment variable. +It is not used in conjunction with +.B \-f +or +.BR \-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. +.TP +.BI \-r\ prompt \fR,\ \fB\-\-prompt= prompt +If a recent version of +.B less +is used as the pager, +.B %man% +will attempt to set its prompt and some sensible options. +The default prompt looks like + +.BI " Manual page" " name" ( sec ") line" " x" + +where +.I name +denotes the manual page name, +.I sec +denotes the section it was found under and +.I x +the current line number. +.\"The default options are +.\".BR \-six8 . +This is achieved by using the +.RB $ LESS +environment variable. +.\"The actual default will depend on your chosen +.\".BR locale . + +Supplying +.B \-r +with a string will override this default. +.\"You may need to do this if your +.\"version of +.\".B less +.\"rejects the default options or if you prefer a different prompt. +The string may contain the text +.B $MAN_PN +which will be expanded to the name of the current manual page and its +section name surrounded by "(" and ")". +The string used to produce the default could be expressed as + +.B \e\ Manual\e\ page\e\ \e$MAN_PN\e\ ?ltline\e\ %lt?L/%L.: +.br +.B byte\e\ %bB?s/%s..?\e\ (END):?pB\e\ %pB\e\e%.. +.br +.B (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 +.BR 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 +.B %man% +sets the +.B \-ix8 +options. + +The +.RB $ MANLESS +environment variable described below may be used to set a default prompt +string if none is supplied on the command line. +.TP +.if !'po4a'hide' .BR \-7 ", " \-\-ascii +When viewing a pure +.IR ascii (7) +manual page on a 7 bit terminal or terminal emulator, some characters may +not display correctly when using the +.IR latin1 (7) +device description with +.B GNU +.BR nroff . +This option allows pure +.I ascii +manual pages to be displayed in +.I ascii +with the +.I latin1 +device. +It will not translate any +.I latin1 +text. +The following table shows the translations performed: some parts of it may +only be displayed properly when using +.B GNU +.BR nroff 's +.IR latin1 (7) +device. + +.ie c \[shc] \ +. ds softhyphen \[shc] +.el \ +. ds softhyphen \(hy +.na +.TS +tab (@); +l c c c. +Description@Octal@latin1@ascii +_ +T{ +continuation hyphen +T}@255@\*[softhyphen]@- +T{ +bullet (middle dot) +T}@267@\(bu@o +T{ +acute accent +T}@264@\(aa@' +T{ +multiplication sign +T}@327@\(mu@x +.TE +.ad + +If the +.I latin1 +column displays correctly, your terminal may be set up for +.I latin1 +characters and this option is not necessary. +If the +.I latin1 +and +.I ascii +columns are identical, you are reading this page using this option or +.B %man% +did not format this page using the +.I latin1 +device description. +If the +.I latin1 +column is missing or corrupt, you may need to view manual pages with this +option. + +This option is ignored when using options +.BR \-t , +.BR \-H , +.BR \-T , +or +.B \-Z +and may be useless for +.B nroff +other than +.BR GNU's . +.TP +.BI \-E\ encoding\fR,\ \fI \-\-encoding\fR=\fIencoding +Generate output for a character encoding other than the default. +For backward compatibility, +.I encoding +may be an +.B nroff +device such as +.BR ascii ", " latin1 ", or " utf8 +as well as a true character encoding such as +.BR UTF\-8 . +.TP +.if !'po4a'hide' .BR \-\-no\-hyphenation ", " \-\-nh +Normally, +.B 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 +.B nroff +from hyphenating a word at an inappropriate point, do not use this option, +but consult the +.B nroff +documentation instead; for instance, you can put "\e%" inside a word to +indicate that it may be hyphenated at that point, or put "\e%" at the start +of a word to prevent it from being hyphenated. +.TP +.if !'po4a'hide' .BR \-\-no\-justification ", " \-\-nj +Normally, +.B 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 +.B nroff +from justifying certain paragraphs, do not use this option, but consult the +.B nroff +documentation instead; for instance, you can use the ".na", ".nf", ".fi", +and ".ad" requests to temporarily disable adjusting and filling. +.TP +.BI \-p\ string \fR,\ \fB\-\-preprocessor= string +Specify the sequence of preprocessors to run before +.B nroff +or +.BR troff / groff . +Not all installations will have a full set of preprocessors. +Some of the preprocessors and the letters used to designate them are: +.BR eqn " (" e ), +.BR grap " (" g ), +.BR pic " (" p ), +.BR tbl " (" t ), +.BR vgrind " (" v ), +.BR refer " (" r ). +This option overrides the +.RB $ MANROFFSEQ +environment variable. +.B %zsoelim% +is always run as the very first preprocessor. +.TP +.if !'po4a'hide' .BR \-t ", " \-\-troff +Use +.I %troff% +to format the manual page to stdout. +This option is not required in conjunction with +.BR \-H , +.BR \-T , +or +.BR \-Z . +.TP +\fB\-T\fP[\fIdevice\/\fP], \fB\-\-troff\-device\fP[=\fIdevice\/\fP] +This option is used to change +.B groff +(or possibly +.BR troff's ) +output to be suitable for a device other than the default. +It implies +.BR \-t . +Examples (provided with Groff-1.17) include +.BR dvi ", " latin1 ", " ps ", " utf8 , +.BR X75 " and " X100 . +.TP +\fB\-H\fP[\fIbrowser\/\fP], \fB\-\-html\fP[=\fIbrowser\/\fP] +This option will cause +.B groff +to produce HTML output, and will display that output in a web browser. +The choice of browser is determined by the optional +.I browser +argument if one is provided, by the +.RB $ BROWSER +environment variable, or by a compile-time default if that is unset (usually +.BR lynx ). +This option implies +.BR \-t , +and will only work with +.B GNU +.BR troff . +.TP +\fB\-X\fP[\fIdpi\/\fP], \fB\-\-gxditview\fP[=\fIdpi\/\fP] +This option displays the output of +.B groff +in a graphical window using the +.B gxditview +program. +The +.I 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 +.B \-T +with the X75, X75-12, X100, or X100-12 device respectively. +.TP +.if !'po4a'hide' .BR \-Z ", " \-\-ditroff +.B groff +will run +.B troff +and then use an appropriate post-processor to produce output suitable for +the chosen device. +If +.I %troff% +is +.BR groff , +this option is passed to +.B groff +and will suppress the use of a post-processor. +It implies +.BR \-t . +.SS "Getting help" +.TP +.if !'po4a'hide' .BR \-? ", " \-\-help +Print a help message and exit. +.TP +.if !'po4a'hide' .B \-\-usage +Print a short usage message and exit. +.TP +.if !'po4a'hide' .BR \-V ", " \-\-version +Display version information. +.SH "EXIT STATUS" +.TP +.if !'po4a'hide' .B 0 +Successful program execution. +.TP +.if !'po4a'hide' .B 1 +Usage, syntax or configuration file error. +.TP +.if !'po4a'hide' .B 2 +Operational error. +.TP +.if !'po4a'hide' .B 3 +A child process returned a non-zero exit status. +.TP +.if !'po4a'hide' .B 16 +At least one of the pages/files/keywords didn't exist or wasn't matched. +.SH ENVIRONMENT +.\".TP \w'MANROFFSEQ\ \ 'u +.TP +.if !'po4a'hide' .B MANPATH +If +.RB $ MANPATH +is set, its value is used as the path to search for manual pages. + +See the +.B SEARCH PATH +section of +.BR manpath (5) +for the default behaviour and details of how this environment variable is +handled. +.TP +.if !'po4a'hide' .B MANROFFOPT +Every time +.B man +invokes the formatter +.RB ( nroff , +.BR troff , +or +.BR groff ), +it adds the contents of +.RB $ MANROFFOPT +to the formatter's command line. +.TP +.if !'po4a'hide' .B MANROFFSEQ +If +.RB $ 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. +.TP +.if !'po4a'hide' .B MANSECT +If +.RB $ 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 +"%sections%", +unless overridden by the +.B SECTION +directive in +.IR %manpath_config_file% . +.TP +.if !'po4a'hide' .BR MANPAGER , " PAGER" +If +.RB $ MANPAGER +or +.RB $ PAGER +is set +.RB ($ MANPAGER +is used in preference), its value is used as the name of the program used to +display the manual page. +By default, +.B %pager% +is used, falling back to +.B %cat% +if +.B %pager% +is not found or is not executable. + +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. +.TP +.if !'po4a'hide' .B MANLESS +If +.RB $ MANLESS +is set, its value will be used as the default prompt string for the +.B less +pager, as if it had been passed using the +.B \-r +option (so any occurrences of the text +.B $MAN_PN +will be expanded in the same way). +For example, if you want to set the prompt string unconditionally to +\(lqmy prompt string\(rq, set +.RB $ MANLESS +to +.RB \(oq \-Psmy\ prompt\ string \(cq. +Using the +.B \-r +option overrides this environment variable. +.TP +.if !'po4a'hide' .B BROWSER +If +.RB $ 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 +.B man +.BR \-\-html . +In each command, +.I %s +is replaced by a filename containing the HTML output from +.BR groff , +.I %% +is replaced by a single percent sign (%), and +.I %c +is replaced by a colon (:). +.TP +.if !'po4a'hide' .B SYSTEM +If +.RB $ SYSTEM +is set, it will have the same effect as if it had been specified as the +argument to the +.B \-m +option. +.TP +.if !'po4a'hide' .B MANOPT +If +.RB $ MANOPT +is set, it will be parsed prior to +.B %man%'s +command line and is expected to be in a similar format. +As all of the other +.B %man% +specific environment variables can be expressed as command line options, and +are thus candidates for being included in +.RB $ 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. +.TP +.if !'po4a'hide' .B MANWIDTH +If +.RB $ MANWIDTH +is set, its value is used as the line length for which manual pages should +be formatted. +If it is not set, manual pages will be formatted with a line length +appropriate to the current terminal (using the value of +.RB $ COLUMNS , +and +.BR ioctl (2) +if available, or falling back to 80 characters if neither is available). +Cat pages will only be saved when the default formatting can be used, that +is when the terminal line length is between 66 and 80 characters. +.TP +.if !'po4a'hide' .B 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 +.RB $ MAN_KEEP_FORMATTING +is set to any non-empty value, these formatting characters are retained. +This may be useful for wrappers around +.B %man% +that can interpret formatting characters. +.TP +.if !'po4a'hide' .B 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 +.B groff +often produce relatively minor error messages about typographical problems +such as poor alignment, which are unsightly and generally confusing when +displayed along with the manual page. +However, some users want to see them anyway, so, if +.RB $ MAN_KEEP_STDERR +is set to any non-empty value, error output will be displayed as usual. +.TP +.if !'po4a'hide' .B MAN_DISABLE_SECCOMP +On Linux, +.B %man% +normally confines subprocesses that handle untrusted data using a +.BR seccomp (2) +sandbox. +This makes it safer to run complex parsing code over arbitrary manual pages. +If this goes wrong for some reason unrelated to the content of the page +being displayed, you can set +.RB $ MAN_DISABLE_SECCOMP +to any non-empty value to disable the sandbox. +.TP +.if !'po4a'hide' .B PIPELINE_DEBUG +If the +.RB $ PIPELINE_DEBUG +environment variable is set to "1", then +.B %man% +will print debugging messages to standard error describing each subprocess +it runs. +.TP +.if !'po4a'hide' .BR LANG , " LC_MESSAGES" +Depending on system and implementation, either or both of +.RB $ LANG +and +.RB $ LC_MESSAGES +will be interrogated for the current message locale. +.B %man% +will display its messages in that locale (if available). +See +.BR setlocale (3) +for precise details. +.SH FILES +.TP +.if !'po4a'hide' .I %manpath_config_file% +man-db configuration file. +.TP +.if !'po4a'hide' .I /usr/share/man +A global manual page hierarchy. +.SH "SEE ALSO" +.if !'po4a'hide' .BR %apropos% (1), +.if !'po4a'hide' .BR groff (1), +.if !'po4a'hide' .BR less (1), +.if !'po4a'hide' .BR %manpath% (1), +.if !'po4a'hide' .BR nroff (1), +.if !'po4a'hide' .BR troff (1), +.if !'po4a'hide' .BR %whatis% (1), +.if !'po4a'hide' .BR %zsoelim% (1), +.if !'po4a'hide' .BR manpath (5), +.if !'po4a'hide' .BR man (7), +.if !'po4a'hide' .BR %catman% (8), +.if !'po4a'hide' .BR %mandb% (8) +.PP +Documentation for some packages may be available in other formats, such as +.BR info (1) +or HTML. +.SH HISTORY +1990, 1991 \(en 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 \(en 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 \(en 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 \(en present day: Colin Watson <cjwatson@debian.org> is now +developing and maintaining man-db. +.SH BUGS +.if !'po4a'hide' https://gitlab.com/man-db/man-db/-/issues +.br +.if !'po4a'hide' https://savannah.nongnu.org/bugs/?group=man-db |