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MAN(7)						       BSD Miscellaneous Information Manual						    MAN(7)

NAME
man -- legacy formatting language for manual pages DESCRIPTION
Traditionally, the man language has been used to write UNIX manuals for the man(1) utility. It supports limited control of presentational details like fonts, indentation and spacing. This reference document describes the structure of manual pages and the syntax and usage of the man language. Do not use man to write your manuals: It lacks support for semantic markup. Use the mdoc(7) language, instead. In a man document, lines beginning with the control character '.' are called ``macro lines''. The first word is the macro name. It usually consists of two capital letters. For a list of available macros, see MACRO OVERVIEW. The words following the macro name are arguments to the macro. Lines not beginning with the control character are called ``text lines''. They provide free-form text to be printed; the formatting of the text depends on the respective processing context: .SH Macro lines change control state. Text lines are interpreted within the current state. Many aspects of the basic syntax of the man language are based on the roff(7) language; see the LANGUAGE SYNTAX and MACRO SYNTAX sections in the roff(7) manual for details, in particular regarding comments, escape sequences, whitespace, and quoting. MANUAL STRUCTURE
Each man document must contain the TH macro describing the document's section and title. It may occur anywhere in the document, although conventionally it appears as the first macro. Beyond TH, at least one macro or text line must appear in the document. The following is a well-formed skeleton man file for a utility "progname": .TH PROGNAME 1 2009-10-10 .SH NAME fBprognamefR (en one line about what it does ." .SH LIBRARY ." For sections 2, 3, and 9 only. ." Not used in OpenBSD. .SH SYNOPSIS fBprognamefR [fB-optionsfR] fIfile ...fR .SH DESCRIPTION The fBfoofR utility processes files ... ." .Sh CONTEXT ." For section 9 functions only. ." .SH IMPLEMENTATION NOTES ." Not used in OpenBSD. ." .SH RETURN VALUES ." For sections 2, 3, and 9 function return values only. ." .SH ENVIRONMENT ." For sections 1, 6, 7, and 8 only. ." .SH FILES ." .SH EXIT STATUS ." For sections 1, 6, and 8 only. ." .SH EXAMPLES ." .SH DIAGNOSTICS ." For sections 1, 4, 6, 7, 8, and 9 printf/stderr messages only. ." .SH ERRORS ." For sections 2, 3, 4, and 9 errno settings only. ." .SH SEE ALSO ." .BR foobar ( 1 ) ." .SH STANDARDS ." .SH HISTORY ." .SH AUTHORS ." .SH CAVEATS ." .SH BUGS ." .SH SECURITY CONSIDERATIONS ." Not used in OpenBSD. The sections in a man document are conventionally ordered as they appear above. Sections should be composed as follows: NAME The name(s) and a short description of the documented material. The syntax for this is generally as follows: fBnamefR (en description LIBRARY The name of the library containing the documented material, which is assumed to be a function in a section 2 or 3 manual. For func- tions in the C library, this may be as follows: Standard C Library (libc, -lc) SYNOPSIS Documents the utility invocation syntax, function call syntax, or device configuration. For the first, utilities (sections 1, 6, and 8), this is generally structured as follows: fBnamefR [-fBabfR] [-fBcfRfIargfR] fBpathfR... For the second, function calls (sections 2, 3, 9): .B char *name(char *fIargfR); And for the third, configurations (section 4): .B name* at cardbus? function? Manuals not in these sections generally don't need a SYNOPSIS. DESCRIPTION This expands upon the brief, one-line description in NAME. It usually contains a break-down of the options (if documenting a command). CONTEXT This section lists the contexts in which functions can be called in section 9. The contexts are autoconf, process, or interrupt. IMPLEMENTATION NOTES Implementation-specific notes should be kept here. This is useful when implementing standard functions that may have side effects or notable algorithmic implications. RETURN VALUES This section documents the return values of functions in sections 2, 3, and 9. ENVIRONMENT Documents any usages of environment variables, e.g., environ(7). FILES Documents files used. It's helpful to document both the file name and a short description of how the file is used (created, modified, etc.). EXIT STATUS This section documents the command exit status for section 1, 6, and 8 utilities. Historically, this information was described in DIAGNOSTICS, a practise that is now discouraged. EXAMPLES Example usages. This often contains snippets of well-formed, well-tested invocations. Make sure that examples work properly! DIAGNOSTICS Documents error conditions. In section 4 and 9 manuals, these are usually messages printed by the kernel to the console and to the kernel log. In section 1, 6, 7, and 8, these are usually messages printed by userland programs to the standard error output. Historically, this section was used in place of EXIT STATUS for manuals in sections 1, 6, and 8; however, this practise is discouraged. ERRORS Documents errno(2) settings in sections 2, 3, 4, and 9. SEE ALSO References other manuals with related topics. This section should exist for most manuals. .BR bar ( 1 ), Cross-references should conventionally be ordered first by section, then alphabetically. STANDARDS References any standards implemented or used, such as IEEE Std 1003.2 ((lqPOSIX.2(rq) If not adhering to any standards, the HISTORY section should be used. HISTORY A brief history of the subject, including where support first appeared. AUTHORS Credits to the person or persons who wrote the code and/or documentation. Authors should generally be noted by both name and email address. CAVEATS Common misuses and misunderstandings should be explained in this section. BUGS Known bugs, limitations, and work-arounds should be described in this section. SECURITY CONSIDERATIONS Documents any security precautions that operators should consider. MACRO OVERVIEW
This overview is sorted such that macros of similar purpose are listed together, to help find the best macro for any given purpose. Depre- cated macros are not included in the overview, but can be found in the alphabetical reference below. Page header and footer meta-data TH set the title: title section date [source [volume]] AT display AT&T UNIX version in the page footer (<= 1 argument) UC display BSD version in the page footer (<= 1 argument) Sections and paragraphs SH section header (one line) SS subsection header (one line) PP, LP, P start an undecorated paragraph (no arguments) RS, RE reset the left margin: [width] IP indented paragraph: [head [width]] TP tagged paragraph: [width] HP hanged paragraph: [width] PD set vertical paragraph distance: [height] br force output line break in text mode (no arguments) sp force vertical space: [height] fi, nf fill mode and no-fill mode (no arguments) in additional indent: [width] Physical markup B boldface font I italic font R roman (default) font SB small boldface font SM small roman font BI alternate between boldface and italic fonts BR alternate between boldface and roman fonts IB alternate between italic and boldface fonts IR alternate between italic and roman fonts RB alternate between roman and boldface fonts RI alternate between roman and italic fonts MACRO REFERENCE
This section is a canonical reference to all macros, arranged alphabetically. For the scoping of individual macros, see MACRO SYNTAX. AT Sets the volume for the footer for compatibility with man pages from AT&T UNIX releases. The optional arguments specify which release it is from. B Text is rendered in bold face. See also I and R. BI Text is rendered alternately in bold face and italic. Thus, '.BI this word and that' causes 'this' and 'and' to render in bold face, while 'word' and 'that' render in italics. Whitespace between arguments is omitted in output. Examples: .BI bold italic bold italic The output of this example will be emboldened ``bold'' and italicised ``italic'', with spaces stripped between arguments. See also IB, BR, RB, RI, and IR. BR Text is rendered alternately in bold face and roman (the default font). Whitespace between arguments is omitted in output. See BI for an equivalent example. See also BI, IB, RB, RI, and IR. DT Has no effect. Included for compatibility. EE This is a non-standard GNU extension, included only for compatibility. In mandoc(1), it does the same as fi. EX This is a non-standard GNU extension, included only for compatibility. In mandoc(1), it does the same as nf. HP Begin a paragraph whose initial output line is left-justified, but subsequent output lines are indented, with the following syntax: .HP [width] The width argument is a roff(7) scaling width. If specified, it's saved for later paragraph left-margins; if unspecified, the saved or default width is used. See also IP, LP, P, PP, and TP. I Text is rendered in italics. See also B and R. IB Text is rendered alternately in italics and bold face. Whitespace between arguments is omitted in output. See BI for an equivalent example. See also BI, BR, RB, RI, and IR. IP Begin an indented paragraph with the following syntax: .IP [head [width]] The width argument is a roff(7) scaling width defining the left margin. It's saved for later paragraph left-margins; if unspecified, the saved or default width is used. The head argument is used as a leading term, flushed to the left margin. This is useful for bulleted paragraphs and so on. See also HP, LP, P, PP, and TP. IR Text is rendered alternately in italics and roman (the default font). Whitespace between arguments is omitted in output. See BI for an equivalent example. See also BI, IB, BR, RB, and RI. LP Begin an undecorated paragraph. The scope of a paragraph is closed by a subsequent paragraph, sub-section, section, or end of file. The saved paragraph left-margin width is reset to the default. See also HP, IP, P, PP, and TP. OP Optional command-line argument. This is a non-standard GNU extension, included only for compatibility. It has the following syntax: .OP key [value] The key is usually a command-line flag and value its argument. P Synonym for LP. See also HP, IP, LP, PP, and TP. PD Specify the vertical space to be inserted before each new paragraph. The syntax is as follows: .PD [height] The height argument is a roff(7) scaling width. It defaults to 1v. If the unit is omitted, v is assumed. This macro affects the spacing before any subsequent instances of HP, IP, LP, P, PP, SH, SS, and TP. PP Synonym for LP. See also HP, IP, LP, P, and TP. R Text is rendered in roman (the default font). See also I and B. RB Text is rendered alternately in roman (the default font) and bold face. Whitespace between arguments is omitted in output. See BI for an equivalent example. See also BI, IB, BR, RI, and IR. RE Explicitly close out the scope of a prior RS. The default left margin is restored to the state of the original RS invocation. RI Text is rendered alternately in roman (the default font) and italics. Whitespace between arguments is omitted in output. See BI for an equivalent example. See also BI, IB, BR, RB, and IR. RS Temporarily reset the default left margin. This has the following syntax: .RS [width] The width argument is a roff(7) scaling width. If not specified, the saved or default width is used. See also RE. SB Text is rendered in small size (one point smaller than the default font) bold face. SH Begin a section. The scope of a section is only closed by another section or the end of file. The paragraph left-margin width is reset to the default. SM Text is rendered in small size (one point smaller than the default font). SS Begin a sub-section. The scope of a sub-section is closed by a subsequent sub-section, section, or end of file. The paragraph left-margin width is reset to the default. TH Sets the title of the manual page with the following syntax: .TH title section date [source [volume]] Conventionally, the document title is given in all caps. The recommended date format is YYYY-MM-DD as specified in the ISO-8601 standard; if the argument does not conform, it is printed verbatim. If the date is empty or not specified, the current date is used. The optional source string specifies the organisation providing the utility. The volume string replaces the default rendered volume, which is dictated by the manual section. Examples: .TH CVS 5 1992-02-12 GNU TP Begin a paragraph where the head, if exceeding the indentation width, is followed by a newline; if not, the body follows on the same line after a buffer to the indentation width. Subsequent output lines are indented. The syntax is as follows: .TP [width] The width argument is a roff(7) scaling width. If specified, it's saved for later paragraph left-margins; if unspecified, the saved or default width is used. See also HP, IP, LP, P, and PP. UC Sets the volume for the footer for compatibility with man pages from BSD releases. The optional first argument specifies which release it is from. UE End a uniform resource identifier block. This is a non-standard GNU extension, included only for compatibility. See UE. UR Begin a uniform resource identifier block. This is a non-standard GNU extension, included only for compatibility. It has the following syn- tax: .UR uri link description to be shown .UE br Breaks the current line. Consecutive invocations have no further effect. See also sp. fi End literal mode begun by nf. in Indent relative to the current indentation: .in [width] If width is signed, the new offset is relative. Otherwise, it is absolute. This value is reset upon the next paragraph, section, or sub- section. na Don't align to the right margin. nf Begin literal mode: all subsequent free-form lines have their end of line boundaries preserved. May be ended by fi. Literal mode is implic- itly ended by SH or SS. sp Insert vertical spaces into output with the following syntax: .sp [height] The height argument is a scaling width as described in roff(7). If 0, this is equivalent to the br macro. Defaults to 1, if unspecified. See also br. MACRO SYNTAX
The man macros are classified by scope: line scope or block scope. Line macros are only scoped to the current line (and, in some situations, the subsequent line). Block macros are scoped to the current line and subsequent lines until closed by another block macro. Line Macros Line macros are generally scoped to the current line, with the body consisting of zero or more arguments. If a macro is scoped to the next line and the line arguments are empty, the next line, which must be text, is used instead. Thus: .I foo is equivalent to '.I foo'. If next-line macros are invoked consecutively, only the last is used. If a next-line macro is followed by a non- next-line macro, an error is raised, except for br, sp, and na. The syntax is as follows: .YO [body...] [body...] Macro Arguments Scope Notes AT <=1 current B n next-line BI n current BR n current DT 0 current EE 0 current compat EX 0 current compat I n next-line IB n current IR n current OP 0, 1 current compat PD 1 current R n next-line RB n current RI n current SB n next-line SM n next-line TH >1, <6 current UC <=1 current br 0 current compat fi 0 current compat in 1 current compat na 0 current compat nf 0 current compat sp 1 current compat Macros marked as "compat" are included for compatibility with the significant corpus of existing manuals that mix dialects of roff. These macros should not be used for portable man manuals. Block Macros Block macros comprise a head and body. As with in-line macros, the head is scoped to the current line and, in one circumstance, the next line (the next-line stipulations as in Line Macros apply here as well). The syntax is as follows: .YO [head...] [head...] [body...] The closure of body scope may be to the section, where a macro is closed by SH; sub-section, closed by a section or SS; part, closed by a section, sub-section, or RE; or paragraph, closed by a section, sub-section, part, HP, IP, LP, P, PP, or TP. No closure refers to an explicit block closing macro. As a rule, block macros may not be nested; thus, calling a block macro while another block macro scope is open, and the open scope is not implicitly closed, is syntactically incorrect. Macro Arguments Head Scope Body Scope Notes HP <2 current paragraph IP <3 current paragraph LP 0 current paragraph P 0 current paragraph PP 0 current paragraph RE 0 current none compat RS 1 current part compat SH >0 next-line section SS >0 next-line sub-section TP n next-line paragraph UE 0 current none compat UR 1 current part compat Macros marked "compat" are as mentioned in Line Macros. If a block macro is next-line scoped, it may only be followed by in-line macros for decorating text. Font handling In man documents, both Physical markup macros and roff(7) 'f' font escape sequences can be used to choose fonts. In text lines, the effect of manual font selection by escape sequences only lasts until the next macro invocation; in macro lines, it only lasts until the end of the macro scope. Note that macros like BR open and close a font scope for each argument. COMPATIBILITY
This section mentions some areas of questionable portability between implementations of the man language. More incompatibilities exist. - Do not depend on SH or SS to close out a literal context opened with nf. This behaviour may not be portable. - troff suppresses a newline before ''' macro output; in mandoc, it is an alias for the standard '.' control character. - In page header lines, GNU troff versions up to and including 1.21 only print volume names explicitly specified in the TH macro; mandoc and newer groff print the default volume name corresponding to the section number when no volume is given, like in mdoc(7). The EE, EX, OP, UE, and UR macros are part of the GNU extended man macro set, and may not be portable to non-GNU troff implementations. SEE ALSO
man(1), mandoc(1), eqn(7), mandoc_char(7), mdoc(7), roff(7), tbl(7) HISTORY
The man language first appeared as a macro package for the roff typesetting system in Version 7 AT&T UNIX. It was later rewritten by James Clark as a macro package for groff. Eric S. Raymond wrote the extended man macros for groff in 2007. The stand-alone implementation that is part of the mandoc(1) utility written by Kristaps Dzonsons appeared in OpenBSD 4.6. AUTHORS
This man reference was written by Kristaps Dzonsons <kristaps@bsd.lv>. CAVEATS
Do not use this language. Use mdoc(7), instead. BSD
June 22, 2014 BSD

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