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       man - macros to format man pages


       groff -Tascii -man file ...

       groff -Tps -man file ...

       man [section] title


       This manual page explains the groff an.tmac macro package (often called the man macro package).  This macro package should be used by developers when writing or porting man pages for Linux.  It is fairly compatible
       with other versions of this macro package, so porting man pages should not be a major problem (exceptions include the NET-2 BSD release, which uses a totally different macro package called mdoc; see mdoc(7)).

       Note that NET-2 BSD mdoc man pages can be used with groff simply by specifying the -mdoc option instead of the -man option.  Using the -mandoc option is, however, recommended, since this will  automatically  detect
       which macro package is in use.

       For conventions that should be employed when writing man pages for the Linux man-pages package, see man-pages(7).

   Title line
       The first command in a man page (after comment lines, that is, lines that start with .\") should be

              .TH title section date source manual

       For details of the arguments that should be supplied to the TH command, see man-pages(7).

       Note that BSD mdoc-formatted pages begin with the Dd command, not the TH command.

       Sections are started with .SH followed by the heading name.

       The only mandatory heading is NAME, which should be the first section and be followed on the next line by a one-line description of the program:

              .SH NAME
              item \- description

       It  is  extremely important that this format is followed, and that there is a backslash before the single dash which follows the item name.  This syntax is used by the mandb(8) program to create a database of short
       descriptions for the whatis(1) and apropos(1) commands.  (See lexgrog(1) for further details on the syntax of the NAME section.)

       For a list of other sections that might appear in a manual page, see man-pages(7).

       The commands to select the type face are:

       .B  Bold

       .BI Bold alternating with italics (especially useful for function specifications)

       .BR Bold alternating with Roman (especially useful for referring to other manual pages)

       .I  Italics

       .IB Italics alternating with bold

       .IR Italics alternating with Roman

       .RB Roman alternating with bold

       .RI Roman alternating with italics

       .SB Small alternating with bold

       .SM Small (useful for acronyms)

       Traditionally, each command can have up to six arguments, but the GNU implementation removes this limitation (you might still want to limit yourself to 6 arguments for portability's sake).  Arguments are  delimited
       by  spaces.   Double  quotes  can  be  used  to specify an argument which contains spaces.  All of the arguments will be printed next to each other without intervening spaces, so that the .BR command can be used to
       specify a word in bold followed by a mark of punctuation in Roman.  If no arguments are given, the command is applied to the following line of text.

   Other macros and strings
       Below are other relevant macros and predefined strings.  Unless noted otherwise, all macros cause a break (end the current line of text).  Many of these macros set or use the "prevailing indent."   The  "prevailing
       indent" value is set by any macro with the parameter i below; macros may omit i in which case the current prevailing indent will be used.  As a result, successive indented paragraphs can use the same indent without
       respecifying the indent value.  A normal (nonindented) paragraph resets the prevailing indent value to its default value (0.5 inches).  By default, a given indent is measured in ens; try to use ens or ems as  units
       for indents, since these will automatically adjust to font size changes.  The other key macro definitions are:

   Normal paragraphs
       .LP      Same as .PP (begin a new paragraph).

       .P       Same as .PP (begin a new paragraph).

       .PP      Begin a new paragraph and reset prevailing indent.

   Relative margin indent
       .RS i    Start  relative  margin  indent:  moves  the  left  margin  i to the right (if i is omitted, the prevailing indent value is used).  A new prevailing indent is set to 0.5 inches.  As a result, all following
                paragraph(s) will be indented until the corresponding .RE.

       .RE      End relative margin indent and restores the previous value of the prevailing indent.

   Indented paragraph macros
       .HP i    Begin paragraph with a hanging indent (the first line of the paragraph is at the left margin of normal paragraphs, and the rest of the paragraph's lines are indented).

       .IP x i  Indented paragraph with optional hanging tag.  If the tag x is omitted, the entire following paragraph is indented by i.  If the tag x is provided, it is hung  at  the  left  margin  before  the  following
                indented paragraph (this is just like .TP except the tag is included with the command instead of being on the following line).  If the tag is too long, the text after the tag will be moved down to the next
                line (text will not be lost or garbled).  For bulleted lists, use this macro with \(bu (bullet) or \(em (em dash) as the tag, and for numbered lists, use the number or letter followed by a  period  as  the
                tag; this simplifies translation to other formats.

       .TP i    Begin paragraph with hanging tag.  The tag is given on the next line, but its results are like those of the .IP command.

   Hypertext link macros
       .UR url
              Insert a hypertext link to the URI (URL) url, with all text up to the following .UE macro as the link text.

       .UE    [trailer]  Terminate  the  link  text of the preceding .UR macro, with the optional trailer (if present, usually a closing parenthesis and/or end-of-sentence punctuation) immediately following.  For non-HTML
              output devices (e.g., man -Tutf8), the link text is followed by the URL in angle brackets; if there is no link text, the URL is printed as its own link text, surrounded by angle  brackets.   (Angle  brackets
              may not be available on all output devices.)  For the HTML output device, the link text is hyperlinked to the URL; if there is no link text, the URL is printed as its own link text.

       These macros have been supported since GNU Troff 1.20 (2009-01-05) and Heirloom Doctools Troff since 160217 (2016-02-17).

   Miscellaneous macros
       .DT      Reset tabs to default tab values (every 0.5 inches); does not cause a break.

       .PD d    Set inter-paragraph vertical distance to d (if omitted, d=0.4v); does not cause a break.

       .SS t    Subheading t (like .SH, but used for a subsection inside a section).

   Predefined strings
       The man package has the following predefined strings:

       \*R    Registration Symbol: ®

       \*S    Change to default font size

       \*(Tm  Trademark Symbol: ™

       \*(lq  Left angled double quote: “

       \*(rq  Right angled double quote: ”

   Safe subset
       Although  technically  man  is  a  troff  macro package, in reality a large number of other tools process man page files that don't implement all of troff's abilities.  Thus, it's best to avoid some of troff's more
       exotic abilities where possible to permit these other tools to work correctly.  Avoid using the various troff preprocessors (if you must, go ahead and use tbl(1), but try to use the IP and TP commands  instead  for
       two-column  tables).   Avoid using computations; most other tools can't process them.  Use simple commands that are easy to translate to other formats.  The following troff macros are believed to be safe (though in
       many cases they will be ignored by translators): \", ., ad, bp, br, ce, de, ds, el, ie, if, fi, ft, hy, ig, in, na, ne, nf, nh, ps, so, sp, ti, tr.

       You may also use many troff escape sequences (those sequences beginning with \).  When you need to include the backslash character as normal text, use \e.  Other sequences you  may  use,  where  x  or  xx  are  any
       characters and N is any digit, include: \', \`, \-, \., \", \%, \*x, \*(xx, \(xx, \$N, \nx, \n(xx, \fx, and \f(xx.  Avoid using the escape sequences for drawing graphics.

       Do  not use the optional parameter for bp (break page).  Use only positive values for sp (vertical space).  Don't define a macro (de) with the same name as a macro in this or the mdoc macro package with a different
       meaning; it's likely that such redefinitions will be ignored.  Every positive indent (in) should be paired with a matching negative indent (although you should be using the RS and RE macros instead).  The condition
       test  (if,ie) should only have 't' or 'n' as the condition.  Only translations (tr) that can be ignored should be used.  Font changes (ft and the \f escape sequence) should only have the values 1, 2, 3, 4, R, I, B,
       P, or CW (the ft command may also have no parameters).

       If you use capabilities beyond these, check the results carefully on several tools.  Once you've confirmed that the additional capability is safe, let the maintainer of this document know about the safe command  or
       sequence that should be added to this list.




       By  all  means  include  full  URLs (or URIs) in the text itself; some tools such as man2html(1) can automatically turn them into hypertext links.  You can also use the UR and UE macros to identify links to related
       information.  If you include URLs, use the full URL (e.g., ⟨⟩) to ensure that tools can automatically find the URLs.

       Tools processing these files should open the file and examine the first nonwhitespace character.  A period (.) or single quote (') at the beginning of a line indicates a troff-based file (such as man or  mdoc).   A
       left angle bracket (<) indicates an SGML/XML-based file (such as HTML or Docbook).  Anything else suggests simple ASCII text (e.g., a "catman" result).

       Many man pages begin with ´\" followed by a space and a list of characters, indicating how the page is to be preprocessed.  For portability's sake to non-troff translators we recommend that you avoid using anything
       other than tbl(1), and Linux can detect that automatically.  However, you might want to include this information so your man page can be handled by other (less capable) systems.  Here are  the  definitions  of  the
       preprocessors invoked by these characters:

       e  eqn(1)

       g  grap(1)

       p  pic(1)

       r  refer(1)

       t  tbl(1)

       v  vgrind(1)


       Most  of  the  macros describe formatting (e.g., font type and spacing) instead of marking semantic content (e.g., this text is a reference to another page), compared to formats like mdoc and DocBook (even HTML has
       more semantic markings).  This situation makes it harder to vary the man format for different media, to make the formatting consistent for a given media, and to automatically insert cross-references.   By  sticking
       to the safe subset described above, it should be easier to automate transitioning to a different reference page format in the future.

       The Sun macro TX is not implemented.


       apropos(1), groff(1), lexgrog(1), man(1), man2html(1), groff_mdoc(7), whatis(1), groff_man(7), groff_www(7), man-pages(7), mdoc(7)


       This  page  is  part  of  release  4.14  of  the  Linux  man-pages  project.   A  description  of  the  project,  information  about  reporting  bugs,  and  the  latest  version  of  this  page,  can  be  found  at