GROFF_MDOC(7)        BSD Miscellaneous Information Manual        GROFF_MDOC(7)

NAME
     groff_mdoc -- reference for groff's mdoc implementation

SYNOPSIS
     groff -mdoc file ...

DESCRIPTION
     A complete reference for writing UNIX manual pages with
     the -mdoc macro package; a content-based and domain-based
     formatting package for GNU troff(1).  Its predecessor, the
     -man(7) package, addressed page layout leaving the manipu-
     lation of fonts and other typesetting details to the indi-
     vidual author.  In -mdoc, page layout macros make up the
     page structure domain which consists of macros for titles,
     section headers, displays and lists - essentially items
     which affect the physical position of text on a formatted
     page.  In addition to the page structure domain, there are
     two more domains, the manual domain and the general text
     domain.  The general text domain is defined as macros
     which perform tasks such as quoting or emphasizing pieces
     of text.  The manual domain is defined as macros that are
     a subset of the day to day informal language used to
     describe commands, routines and related UNIX files.
     Macros in the manual domain handle command names, command
     line arguments and options, function names, function
     parameters, pathnames, variables, cross references to
     other manual pages, and so on.  These domain items have
     value for both the author and the future user of the man-
     ual page.  Hopefully, the consistency gained across the
     manual set will provide easier translation to future docu-
     mentation tools.

     Throughout the UNIX manual pages, a manual entry is simply
     referred to as a man page, regardless of actual length and
     without sexist intention.

GETTING STARTED
     The material presented in the remainder of this document
     is outlined as follows:

           1.   TROFF IDIOSYNCRASIES
                Macro Usage
                Passing Space Characters in an Argument
                Trailing Blank Space Characters
                Escaping Special Characters
                Other Possible Pitfalls

           2.   A MANUAL PAGE TEMPLATE

           3.   CONVENTIONS

           4.   TITLE MACROS

           5.   INTRODUCTION OF MANUAL AND GENERAL TEXT DOMAINS
                What's in a Name...
                General Syntax

           6.   MANUAL DOMAIN
                Addresses
                Author Name
                Arguments
                Configuration Declarations (Section Four Only)
                Command Modifiers
                Defined Variables
                Errno's
                Environment Variables
                Flags
                Function Declarations
                Function Types
                Functions (Library Routines)
                Function Arguments
                Return Values
                Exit Status
                Interactive Commands
                Library Names
                Literals
                Names
                Options
                Pathnames
                Standards
                Variable Types
                Variables
                Manual Page Cross References

           7.   GENERAL TEXT DOMAIN
                AT&T Macro
                BSD Macro
                NetBSD Macro
                FreeBSD Macro
                DragonFly Macro
                OpenBSD Macro
                BSD/OS Macro
                UNIX Macro
                Emphasis Macro
                Font Mode
                Enclosure and Quoting Macros
                No-Op or Normal Text Macro
                No-Space Macro
                Section Cross References
                Symbolics
                Mathematical Symbols
                References and Citations
                Trade Names (or Acronyms and Type Names)
                Extended Arguments

           8.   PAGE STRUCTURE DOMAIN
                Section Headers
                Subsection Headers
                Paragraphs and Line Spacing
                Keeps
                Examples and Displays
                Lists and Columns

           9.   MISCELLANEOUS MACROS

           10.  PREDEFINED STRINGS

           11.  DIAGNOSTICS

           12.  FORMATTING WITH GROFF, TROFF, AND NROFF

           13.  FILES

           14.  SEE ALSO

           15.  BUGS

TROFF IDIOSYNCRASIES
     The -mdoc package attempts to simplify the process of
     writing a man page.  Theoretically, one should not have to
     learn the tricky details of GNU troff(1) to use -mdoc;
     however, there are a few limitations which are unavoidable
     and best gotten out of the way.  And, too, be forewarned,
     this package is not fast.

   Macro Usage
     As in GNU troff(1), a macro is called by placing a `.'
     (dot character) at the beginning of a line followed by the
     two-character (or three-character) name for the macro.
     There can be space or tab characters between the dot and
     the macro name.  Arguments may follow the macro separated
     by spaces (but no tabs).  It is the dot character at the
     beginning of the line which causes GNU troff(1) to inter-
     pret the next two (or more) characters as a macro name.  A
     single starting dot followed by nothing is ignored.  To
     place a `.' (dot character) at the beginning of an input
     line in some context other than a macro invocation, pre-
     cede the `.' (dot) with the `\&' escape sequence which
     translates literally to a zero-width space, and is never
     displayed in the output.

     In general, GNU troff(1) macros accept an unlimited number
     of arguments (contrary to other versions of troff which
     can't handle more than nine arguments).  In limited cases,
     arguments may be continued or extended on the next line
     (See Extended Arguments below).  Almost all macros handle
     quoted arguments (see Passing Space Characters in an
     Argument below).

     Most of the -mdoc general text domain and manual domain
     macros are special in that their argument lists are parsed
     for callable macro names.  This means an argument on the
     argument list which matches a general text or manual
     domain macro name (and which is defined to be callable)
     will be executed or called when it is processed.  In this
     case the argument, although the name of a macro, is not
     preceded by a `.' (dot).  This makes it possible to nest
     macros; for example the option macro, `.Op', may call the
     flag and argument macros, `Fl' and `Ar', to specify an
     optional flag with an argument:

           [-s bytes]  is produced by `.Op Fl s Ar bytes'

     To prevent a string from being interpreted as a macro
     name, precede the string with the escape sequence `\&':

           [Fl s Ar bytes]  is produced by `.Op \&Fl s \&Ar
                            bytes'

     Here the strings `Fl' and `Ar' are not interpreted as
     macros.  Macros whose argument lists are parsed for
     callable arguments are referred to as parsed and macros
     which may be called from an argument list are referred to
     as callable throughout this document.  This is a technical
     faux pas as almost all of the macros in -mdoc are parsed,
     but as it was cumbersome to constantly refer to macros as
     being callable and being able to call other macros, the
     term parsed has been used.

     In the following, we call an -mdoc macro which starts a
     line (with a leading dot) a command if this distinction is
     necessary.

   Passing Space Characters in an Argument
     Sometimes it is desirable to give as an argument a string
     containing one or more blank space characters, say, to
     specify arguments to commands which expect particular
     arrangement of items in the argument list.  Additionally,
     it makes -mdoc working faster.  For example, the function
     command `.Fn' expects the first argument to be the name of
     a function and any remaining arguments to be function
     parameters.  As ANSI C stipulates the declaration of func-
     tion parameters in the parenthesized parameter list, each
     parameter is guaranteed to be at minimum a two word
     string.  For example, int foo.

     There are two possible ways to pass an argument which con-
     tains an embedded space.  One way of passing a string con-
     taining blank spaces is to use the hard or unpaddable
     space character `\ ', that is, a blank space preceded by
     the escape character `\'.  This method may be used with
     any macro but has the side effect of interfering with the
     adjustment of text over the length of a line.  Troff sees
     the hard space as if it were any other printable character
     and cannot split the string into blank or newline sepa-
     rated pieces as one would expect.  This method is useful
     for strings which are not expected to overlap a line
     boundary.  An alternative is to use `\~', a paddable (i.e.
     stretchable), unbreakable space (this is a GNU troff(1)
     extension).  The second method is to enclose the string
     with double quotes.

     For example:

           fetch(char *str)  is created by `.Fn fetch char\
                             *str'

           fetch(char *str)  can also be created by `.Fn fetch
                             "char *str"'

     If the `\' before the space in the first example or double
     quotes in the second example were omitted, `.Fn' would see
     three arguments, and the result would be:

           fetch(char, *str)

   Trailing Blank Space Characters
     Troff can be confused by blank space characters at the end
     of a line.  It is a wise preventive measure to globally
     remove all blank spaces from <blank-space><end-of-line>
     character sequences.  Should the need arise to use a blank
     character at the end of a line, it may be forced with an
     unpaddable space and the `\&' escape character.  For exam-
     ple, `string\ \&'.

   Escaping Special Characters
     Special characters like the newline character `\n' are
     handled by replacing the `\' with `\e' (e.g. `\en') to
     preserve the backslash.

   Other Possible Pitfalls
     A warning is emitted when an empty input line is found
     outside of displays (see below).  Use `.sp' instead.
     (Well, it is even better to use -mdoc macros to avoid the
     usage of low-level commands.)

     Leading spaces will cause a break and are output directly.
     Avoid this behaviour if possible.  Similarly, do not use
     more than one space character between words in an ordinary
     text line; contrary to other text formatters, they are not
     replaced with a single space.

     You can't pass `"' directly as an argument.  Use `\*[q]'
     (or `\*q') instead.

     By default, troff(1) inserts two space characters after a
     punctuation mark closing a sentence; characters like `)'
     or `'' are treated transparently, not influencing the sen-
     tence-ending behaviour.  To change this, insert `\&'
     before or after the dot:

           The
           .Ql .
           character.
           .Pp
           The
           .Ql \&.
           character.
           .Pp
           .No test .
           test
           .Pp
           .No test.
           test

     gives

           The `'.  character

           The `.' character.

           test.  test

           test. test

     As can be seen in the first and third line, -mdoc handles
     punctuation characters specially in macro arguments.  This
     will be explained in section General Syntax below.  In the
     same way, you have to protect trailing full stops of
     abbreviations with a trailing zero-width space: `e.g.\&'.

     A comment in the source file of a man page can be either
     started with `.\"' on a single line, `\"' after some
     input, or `\#' anywhere (the latter is a GNU troff(1)
     extension); the rest of such a line is ignored.

A MANUAL PAGE TEMPLATE
     The body of a man page is easily constructed from a basic
     template:

           .\" The following commands are required for all man pages.
           .Dd Month day, year
           .Os [OPERATING_SYSTEM] [version/release]
           .Dt DOCUMENT_TITLE [section number] [architecture/volume]
           .Sh NAME
           .Nm name
           .Nd one line description of name
           .\" This next command is for sections 2 and 3 only.
           .\" .Sh LIBRARY
           .Sh SYNOPSIS
           .Sh DESCRIPTION
           .\" The following commands should be uncommented and
           .\" used where appropriate.
           .\" .Sh IMPLEMENTATION NOTES
           .\" This next command is for sections 2, 3 and 9 function
           .\" return values only.
           .\" .Sh RETURN VALUES
           .\" This next command is for sections 1, 6, 7 and 8 only.
           .\" .Sh ENVIRONMENT
           .\" .Sh FILES
           .\" .Sh EXAMPLES
           .\" This next command is for sections 1, 6, 7, 8 and 9 only
           .\"     (command return values (to shell) and
           .\"     fprintf/stderr type diagnostics).
           .\" .Sh DIAGNOSTICS
           .\" .Sh COMPATIBILITY
           .\" This next command is for sections 2, 3 and 9 error
           .\"     and signal handling only.
           .\" .Sh ERRORS
           .\" .Sh SEE ALSO
           .\" .Sh STANDARDS
           .\" .Sh HISTORY
           .\" .Sh AUTHORS
           .\" .Sh BUGS

     The first items in the template are the commands `.Dd',
     `.Os', and `.Dt'; the document date, the operating system
     the man page or subject source is developed or modified
     for, and the man page title (in upper case) along with the
     section of the manual the page belongs in.  These commands
     identify the page and are discussed below in TITLE MACROS.

     The remaining items in the template are section headers
     (.Sh); of which NAME, SYNOPSIS, and DESCRIPTION are manda-
     tory.  The headers are discussed in PAGE STRUCTURE DOMAIN,
     after presentation of MANUAL DOMAIN.  Several content
     macros are used to demonstrate page layout macros; reading
     about content macros before page layout macros is recom-
     mended.

CONVENTIONS
     In the description of all macros below, optional arguments
     are put into brackets.  An ellipsis (`...') represents
     zero or more additional arguments.  Alternative values for
     a parameter are separated with `|'.  If there are alterna-
     tive values for a mandatory parameter, braces are used
     (together with `|') to enclose the value set.  Meta-vari-
     ables are specified within angles.

     Example:

           .Xx <foo> {bar1 | bar2} [-test1 [-test2 | -test3]]
                   ...

     Except stated explicitly, all macros are parsed and
     callable.

     Note that a macro takes effect up to the next nested
     macro.  For example, `.Ic foo Aq bar' doesn't produce `foo
     <bar>' but `foo <bar>'.  Consequently, a warning message
     is emitted for most commands if the first argument is a
     macro itself since it cancels the effect of the calling
     command completely.  Another consequence is that quoting
     macros never insert literal quotes; `foo <bar>' has been
     produced by `.Ic "foo <bar>"'.

     Most macros have a default width value which can be used
     to specify a label width (-width) or offset (-offset) for
     the `.Bl' and `.Bd' macros.  It is recommended not to use
     this rather obscure feature to avoid dependencies on local
     modifications of the -mdoc package.

TITLE MACROS
     The title macros are part of the page structure domain but
     are presented first and separately for someone who wishes
     to start writing a man page yesterday.  Three header
     macros designate the document title or manual page title,
     the operating system, and the date of authorship.  These
     macros are called once at the very beginning of the docu-
     ment and are used to construct headers and footers only.

     .Dt [<document title>] [<section number>] [<volume>]
             The document title is the subject of the man page
             and must be in CAPITALS due to troff limitations.
             If omitted, `UNTITLED' is used.  The section num-
             ber may be a number in the range 1, ..., 9 or
             `unass', `draft', or `paper'.  If it is specified,
             and no volume name is given, a default volume name
             is used.

             Under BSD, the following sections are defined:

                   1        BSD General Commands Manual
                   2        BSD System Calls Manual
                   3        BSD Library Functions Manual
                   4        BSD Kernel Interfaces Manual
                   5        BSD File Formats Manual
                   6        BSD Games Manual
                   7        BSD Miscellaneous Information
                            Manual
                   8        BSD System Manager's Manual
                   9        BSD Kernel Developer's Manual

             A volume name may be arbitrary or one of the fol-
             lowing:

                   USD      User's Supplementary Documents
                   PS1      Programmer's Supplementary
                            Documents
                   AMD      Ancestral Manual Documents
                   SMM      System Manager's Manual
                   URM      User's Reference Manual
                   PRM      Programmer's Manual
                   KM       Kernel Manual
                   IND      Manual Master Index
                   LOCAL    Local Manual
                   CON      Contributed Software Manual

             For compatibility, `MMI' can be used for `IND',
             and `LOC' for `LOCAL'.  Values from the previous
             table will specify a new volume name.  If the
             third parameter is a keyword designating a com-
             puter architecture, its value is prepended to the
             default volume name as specified by the second
             parameter.  By default, the following architecture
             keywords are defined:

                   alpha, acorn26, acorn32, algor, amd64,
                   amiga, arc, arm26, arm32, atari, bebox,
                   cats, cesfic, cobalt, dreamcast, evbarm,
                   evbmips, evbppc, evbsh3, hp300, hp700,
                   hpcmips, i386, luna68k, m68k, mac68k,
                   macppc, mips, mmeye, mvme68k, mvmeppc,
                   netwinder, news68k, newsmips, next68k,
                   ofppc, pc532, pmax, pmppc, powerpc, prep,
                   sandpoint, sgimips, sh3, shark, sparc,
                   sparc64, sun3, tahoe, vax, x68k, x86_64

             If the section number is neither a numeric expres-
             sion in the range 1 to 9 nor one of the above
             described keywords, the third parameter is used
             verbatim as the volume name.

             In the following examples, the left (which is
             identical to the right) and the middle part of the
             manual page header strings are shown.  Note how
             `\&' prevents the digit 7 from being a valid
             numeric expression.

                   .Dt FOO 7       `FOO(7)' `BSD Miscellaneous
                                   Information Manual'
                   .Dt FOO 7 bar   `FOO(7)' `BSD Miscellaneous
                                   Information Manual'
                   .Dt FOO \&7 bar
                                   `FOO(7)' `bar'
                   .Dt FOO 2 i386  `FOO(2)' `BSD/i386 System
                                   Calls Manual'
                   .Dt FOO "" bar  `FOO' `bar'

             Local, OS-specific additions might be found in the
             file mdoc.local; look for strings named
             `volume-ds-XXX' (for the former type) and
             `volume-as-XXX' (for the latter type); `XXX' then
             denotes the keyword to be used with the `.Dt'
             macro.

             This macro is neither callable nor parsed.

     .Os [<operating system>] [<release>]
             If the first parameter is empty, the default `BSD'
             is used.  This may be overridden in the local con-
             figuration file, mdoc.local.  In general, the name
             of the operating system should be the common
             acronym, e.g. BSD or ATT.  The release should be
             the standard release nomenclature for the system
             specified.  In the following table, the possible
             second arguments for some predefined operating
             systems are listed.  Similar to `.Dt', local addi-
             tions might be defined in mdoc.local; look for
             strings named `operating-system-XXX-YYY', where
             `XXX' is the acronym for the operating system and
             `YYY' the release ID.

                   ATT      7th, 7, III, 3, V, V.2, V.3, V.4

                   BSD      3, 4, 4.1, 4.2, 4.3, 4.3t, 4.3T,
                            4.3r, 4.3R, 4.4

                   NetBSD   0.8, 0.8a, 0.9, 0.9a, 1.0, 1.0a,
                            1.1, 1.2, 1.2a, 1.2b, 1.2c, 1.2d,
                            1.2e, 1.3, 1.3a, 1.4, 1.4.1, 1.4.2,
                            1.4.3, 1.5, 1.5.1, 1.5.2, 1.5.3,
                            1.6, 1.6.1, 1.6.2, 1.6.3, 2.0,
                            2.0.1, 2.0.2, 2.0.3, 2.1, 3.0,
                            3.0.1, 3.0.2, 3.1, 4.0, 4.0.1

                   FreeBSD  1.0, 1.1, 1.1.5, 1.1.5.1, 2.0,
                            2.0.5, 2.1, 2.1.5, 2.1.6, 2.1.7,
                            2.2, 2.2.1, 2.2.2, 2.2.5, 2.2.6,
                            2.2.7, 2.2.8, 3.0, 3.1, 3.2, 3.3,
                            3.4, 3.5, 4.0, 4.1, 4.1.1, 4.2,
                            4.3, 4.4, 4.5, 4.6, 4.6.2, 4.7,
                            4.8, 4.9, 4.10, 4.11, 5.0, 5.1,
                            5.2, 5.2.1, 5.3, 5.4, 5.5, 6.0,
                            6.1, 6.2, 6.3, 6.4, 7.0, 7.1

                   DragonFly
                            1.0, 1.1, 1.2, 1.3, 1.4, 1.5, 1.6,
                            1.8, 1.8.1, 1.10, 1.12, 1.12.2, 2.0

                   Darwin   8.0.0, 8.1.0, 8.2.0, 8.3.0, 8.4.0,
                            8.5.0, 8.6.0, 8.7.0, 8.8.0, 8.9.0,
                            8.10.0, 8.11.0, 9.0.0, 9.1.0,
                            9.2.0, 9.3.0, 9.4.0, 9.5.0, 9.6.0

             For ATT, an unknown second parameter will be
             replaced with the string UNIX; for the other pre-
             defined acronyms it will be ignored and a warning
             message emitted.  Unrecognized arguments are dis-
             played as given in the page footer.  For instance,
             a typical footer might be:

                   .Os BSD 4.3

             giving `4.3 Berkeley Distribution', or for a
             locally produced set

                   .Os CS Department

             which will produce `CS Department'.

             If the `.Os' macro is not present, the bottom left
             corner of the manual page will be ugly.

             This macro is neither callable nor parsed.

     .Dd [<month> <day>, <year>]
             If `Dd' has no arguments, `Epoch' is used for the
             date string.  If it has exactly three arguments,
             they are concatenated, separated with unbreakable
             space:

                   .Dd January 25, 2001

             The month's name shall not be abbreviated.

             With any other number of arguments, the current
             date is used, ignoring the parameters.

             This macro is neither callable nor parsed.

INTRODUCTION OF MANUAL AND GENERAL TEXT DOMAINS
   What's in a Name...
     The manual domain macro names are derived from the day to
     day informal language used to describe commands, subrou-
     tines and related files.  Slightly different variations of
     this language are used to describe the three different
     aspects of writing a man page.  First, there is the
     description of -mdoc macro command usage.  Second is the
     description of a UNIX command with -mdoc macros, and
     third, the description of a command to a user in the ver-
     bal sense; that is, discussion of a command in the text of
     a man page.

     In the first case, troff(1) macros are themselves a type
     of command; the general syntax for a troff command is:

           .Xx argument1 argument2 ...

     `.Xx' is a macro command, and anything following it are
     arguments to be processed.  In the second case, the
     description of a UNIX command using the content macros is
     a bit more involved; a typical SYNOPSIS command line might
     be displayed as:

           filter [-flag] <infile> <outfile>

     Here, filter is the command name and the bracketed string
     -flag is a flag argument designated as optional by the
     option brackets.  In -mdoc terms, <infile> and <outfile>
     are called meta arguments; in this example, the user has
     to replace the meta expressions given in angle brackets
     with real file names.  Note that in this document meta
     arguments are used to describe -mdoc commands; in most man
     pages, meta variables are not specifically written with
     angle brackets.  The macros which formatted the above
     example:

           .Nm filter
           .Op Fl flag
           .Ao Ar infile Ac Ao Ar outfile Ac

     In the third case, discussion of commands and command syn-
     tax includes both examples above, but may add more detail.
     The arguments <infile> and <outfile> from the example
     above might be referred to as operands or file arguments.
     Some command line argument lists are quite long:

           make  [-eiknqrstv] [-D variable] [-d flags] [-f
                 makefile] [-I directory] [-j max_jobs]
                 [variable=value] [target ...]

     Here one might talk about the command make and qualify the
     argument, makefile, as an argument to the flag, -f, or
     discuss the optional file operand target.  In the verbal
     context, such detail can prevent confusion, however the
     -mdoc package does not have a macro for an argument to a
     flag.  Instead the `Ar' argument macro is used for an op-
     erand or file argument like target as well as an argument
     to a flag like variable.  The make command line was pro-
     duced from:

           .Nm make
           .Op Fl eiknqrstv
           .Op Fl D Ar variable
           .Op Fl d Ar flags
           .Op Fl f Ar makefile
           .Op Fl I Ar directory
           .Op Fl j Ar max_jobs
           .Op Ar variable Ns = Ns Ar value
           .Bk
           .Op Ar target ...
           .Ek

     The `.Bk' and `.Ek' macros are explained in Keeps.

   General Syntax
     The manual domain and general text domain macros share a
     similar syntax with a few minor deviations; most notably,
     `.Ar', `.Fl', `.Nm', and `.Pa' differ only when called
     without arguments; and `.Fn' and `.Xr' impose an order on
     their argument lists.  All content macros are capable of
     recognizing and properly handling punctuation, provided
     each punctuation character is separated by a leading
     space.  If a command is given:

           .Ar sptr, ptr),

     The result is:

           sptr, ptr),

     The punctuation is not recognized and all is output in the
     font used by `.Ar'.  If the punctuation is separated by a
     leading white space:

           .Ar sptr , ptr ) ,

     The result is:

           sptr, ptr),

     The punctuation is now recognized and output in the
     default font distinguishing it from the argument strings.
     To remove the special meaning from a punctuation character
     escape it with `\&'.

     The following punctuation characters are recognized by
     -mdoc:

               .         ,         :         ;         (
               )         [         ]         ?         !

     Troff is limited as a macro language, and has difficulty
     when presented with a string containing a member of the
     mathematical, logical or quotation set:

                 {+,-,/,*,%,<,>,<=,>=,=,==,&,`,',"}

     The problem is that troff may assume it is supposed to
     actually perform the operation or evaluation suggested by
     the characters.  To prevent the accidental evaluation of
     these characters, escape them with `\&'.  Typical syntax
     is shown in the first content macro displayed below,
     `.Ad'.

MANUAL DOMAIN
   Addresses
     The address macro identifies an address construct.

           Usage: .Ad <address> ...

                    .Ad addr1           addr1
                    .Ad addr1 .         addr1.
                    .Ad addr1 , file2   addr1, file2
                    .Ad f1 , f2 , f3 :  f1, f2, f3:
                    .Ad addr ) ) ,      addr)),

     The default width is 12n.

   Author Name
     The `.An' macro is used to specify the name of the author
     of the item being documented, or the name of the author of
     the actual manual page.

           Usage: .An <author name> ...

                    .An "Joe Author"        Joe Author

                    .An "Joe Author" ,      Joe Author,

                    .An "Joe Author" Aq nobody@FreeBSD.org
                                            Joe Author
                                            <nobody@FreeBSD.org>

                    .An "Joe Author" ) ) ,  Joe Author)),

     The default width is 12n.

     In the AUTHORS section, the `.An' command causes a line
     break allowing each new name to appear on its own line.
     If this is not desirable,

           .An -nosplit

     call will turn this off.  To turn splitting back on, write

           .An -split

   Arguments
     The .Ar argument macro may be used whenever an argument is
     referenced.  If called without arguments, the `file ...'
     string is output.

           Usage: .Ar [<argument>] ...

                    .Ar              file ...
                    .Ar file1        file1
                    .Ar file1 .      file1.
                    .Ar file1 file2  file1 file2
                    .Ar f1 f2 f3 :   f1 f2 f3:
                    .Ar file ) ) ,   file)),

     The default width is 12n.

   Configuration Declaration (Section Four Only)
     The `.Cd' macro is used to demonstrate a config(8) decla-
     ration for a device interface in a section four manual.

           Usage: .Cd <argument> ...

                    .Cd "device le0 at scode?"  device le0 at
                                                scode?

     In the SYNOPSIS section a `.Cd' command causes a line
     break before and after its arguments are printed.

     The default width is 12n.

   Command Modifiers
     The command modifier is identical to the `.Fl' (flag) com-
     mand with the exception that the `.Cm' macro does not
     assert a dash in front of every argument.  Traditionally
     flags are marked by the preceding dash, however, some com-
     mands or subsets of commands do not use them.  Command
     modifiers may also be specified in conjunction with inter-
     active commands such as editor commands.  See Flags.

     The default width is 10n.

   Defined Variables
     A variable (or constant) which is defined in an include
     file is specified by the macro `.Dv'.

           Usage: .Dv <defined variable> ...

                    .Dv MAXHOSTNAMELEN  MAXHOSTNAMELEN
                    .Dv TIOCGPGRP )     TIOCGPGRP)

     The default width is 12n.

   Errno's
     The `.Er' errno macro specifies the error return value for
     section 2, 3, and 9 library routines.  The second example
     below shows `.Er' used with the `.Bq' general text domain
     macro, as it would be used in a section two manual page.

           Usage: .Er <errno type> ...

                    .Er ENOENT      ENOENT
                    .Er ENOENT ) ;  ENOENT);
                    .Bq Er ENOTDIR  [ENOTDIR]

     The default width is 17n.

   Environment Variables
     The `.Ev' macro specifies an environment variable.

           Usage: .Ev <argument> ...

                    .Ev DISPLAY        DISPLAY
                    .Ev PATH .         PATH.
                    .Ev PRINTER ) ) ,  PRINTER)),

     The default width is 15n.

   Flags
     The `.Fl' macro handles command line flags.  It prepends a
     dash, `-', to the flag.  For interactive command flags,
     which are not prepended with a dash, the `.Cm' (command
     modifier) macro is identical, but without the dash.

           Usage: .Fl <argument> ...

                    .Fl          -
                    .Fl cfv      -cfv
                    .Fl cfv .    -cfv.
                    .Cm cfv .    cfv.
                    .Fl s v t    -s -v -t
                    .Fl - ,      --,
                    .Fl xyz ) ,  -xyz),
                    .Fl |        - |

     The `.Fl' macro without any arguments results in a dash
     representing stdin/stdout.  Note that giving `.Fl' a sin-
     gle dash will result in two dashes.

     The default width is 12n.

   Function Declarations
     The `.Fd' macro is used in the SYNOPSIS section with sec-
     tion two or three functions.  It is neither callable nor
     parsed.

           Usage: .Fd <argument> ...

                    .Fd "#include <sys/types.h>"  #include
                                                  <sys/types.h>

     In the SYNOPSIS section a `.Fd' command causes a line
     break if a function has already been presented and a break
     has not occurred.  This leaves a nice vertical space in
     between the previous function call and the declaration for
     the next function.

     The `.In' macro, while in the SYNOPSIS section, represents
     the #include statement, and is the short form of the above
     example.  It specifies the C header file as being included
     in a C program.  It also causes a line break.

     While not in the SYNOPSIS section, it represents the
     header file enclosed in angle brackets.

           Usage: .In <header file>

                    .In stdio.h  #include <stdio.h>
                    .In stdio.h  <stdio.h>

   Function Types
     This macro is intended for the SYNOPSIS section.  It may
     be used anywhere else in the man page without problems,
     but its main purpose is to present the function type in
     kernel normal form for the SYNOPSIS of sections two and
     three (it causes a line break, allowing the function name
     to appear on the next line).

           Usage: .Ft <type> ...

                    .Ft struct stat  struct stat

   Functions (Library Routines)
     The `.Fn' macro is modeled on ANSI C conventions.

           Usage: .Fn <function> [<parameter>] ...

                    .Fn getchar              getchar()
                    .Fn strlen ) ,           strlen()),
                    .Fn align "char *ptr" ,  align(char *ptr),

     Note that any call to another macro signals the end of the
     `.Fn' call (it will insert a closing parenthesis at that
     point).

     For functions with many parameters (which is rare), the
     macros `.Fo' (function open) and `.Fc' (function close)
     may be used with `.Fa' (function argument).

     Example:

           .Ft int
           .Fo res_mkquery
           .Fa "int op"
           .Fa "char *dname"
           .Fa "int class"
           .Fa "int type"
           .Fa "char *data"
           .Fa "int datalen"
           .Fa "struct rrec *newrr"
           .Fa "char *buf"
           .Fa "int buflen"
           .Fc

     Produces:

           int res_mkquery(int op, char *dname, int class,
           int type, char *data, int datalen,
           struct rrec *newrr, char *buf, int buflen)

     In the SYNOPSIS section, the function will always begin at
     the beginning of line.  If there is more than one function
     presented in the SYNOPSIS section and a function type has
     not been given, a line break will occur, leaving a nice
     vertical space between the current function name and the
     one prior.

     The default width values of `.Fn' and `.Fo' are 12n and
     16n, respectively.

   Function Arguments
     The `.Fa' macro is used to refer to function arguments
     (parameters) outside of the SYNOPSIS section of the manual
     or inside the SYNOPSIS section if the enclosure macros
     `.Fo' and `.Fc' instead of `.Fn' are used.  `.Fa' may also
     be used to refer to structure members.

           Usage: .Fa <function argument> ...

                    .Fa d_namlen ) ) ,  d_namlen)),
                    .Fa iov_len         iov_len

     The default width is 12n.

   Return Values
     The `.Rv' macro generates text for use in the RETURN
     VALUES section.

           Usage: .Rv [-std] [<function> ...]

     For example, `.Rv -std atexit' produces:

            The atexit() function returns the value 0 if suc-
            cessful; otherwise the value -1 is returned and the
            global variable errno is set to indicate the error.

     The -std option is valid only for manual page sections 2
     and 3.  Currently, this macro does nothing if used without
     the -std flag.

   Exit Status
     The `.Ex' macro generates text for use in the DIAGNOSTICS
     section.

           Usage: .Ex [-std] [<utility> ...]

     For example, `.Ex -std cat' produces:

            The cat utility exits 0 on success, and >0 if an
            error occurs.

     The -std option is valid only for manual page sections 1,
     6 and 8.  Currently, this macro does nothing if used with-
     out the -std flag.

   Interactive Commands
     The `.Ic' macro designates an interactive or internal com-
     mand.

           Usage: .Ic <argument> ...

                    .Ic :wq                :wq
                    .Ic "do while {...}"   do while {...}
                    .Ic setenv , unsetenv  setenv, unsetenv

     The default width is 12n.

   Library Names
     The `.Lb' macro is used to specify the library where a
     particular function is compiled in.

           Usage: .Lb <argument> ...

     Available arguments to `.Lb' and their results are:

           libarm       ARM Architecture Library (libarm,
                        -larm)
           libarm32     ARM32 Architecture Library (libarm32,
                        -larm32)
           libc         Standard C Library (libc, -lc)
           libcdk       Curses Development Kit Library (libcdk,
                        -lcdk)
           libcompat    Compatibility Library (libcompat,
                        -lcompat)
           libcrypt     Crypt Library (libcrypt, -lcrypt)
           libcurses    Curses Library (libcurses, -lcurses)
           libedit      Command Line Editor Library (libedit,
                        -ledit)
           libevent     Event Notification Library (libevent,
                        -levent)
           libform      Curses Form Library (libform, -lform)
           libi386      i386 Architecture Library (libi386,
                        -li386)
           libintl      Internationalized Message Handling
                        Library (libintl, -lintl)
           libipsec     IPsec Policy Control Library (libipsec,
                        -lipsec)
           libkvm       Kernel Data Access Library (libkvm,
                        -lkvm)
           libm         Math Library (libm, -lm)
           libm68k      m68k Architecture Library (libm68k,
                        -lm68k)
           libmagic     Magic Number Recognition Library
                        (libmagic, -lmagic)
           libmenu      Curses Menu Library (libmenu, -lmenu)
           libossaudio  OSS Audio Emulation Library
                        (libossaudio, -lossaudio)
           libpam       Pluggable Authentication Module Library
                        (libpam, -lpam)
           libpcap      Packet Capture Library (libpcap,
                        -lpcap)
           libpci       PCI Bus Access Library (libpci, -lpci)
           libpmc       Performance Counters Library (libpmc,
                        -lpmc)
           libposix     POSIX Compatibility Library (libposix,
                        -lposix)
           libpthread   POSIX Threads Library (libpthread,
                        -lpthread)
           libresolv    DNS Resolver Library (libresolv,
                        -lresolv)
           librt        POSIX Real-time Library (librt, -lrt)
           libtermcap   Termcap Access Library (libtermcap,
                        -ltermcap)
           libusbhid    USB Human Interface Devices Library
                        (libusbhid, -lusbhid)
           libutil      System Utilities Library (libutil,
                        -lutil)
           libx86_64    x86_64 Architecture Library (libx86_64,
                        -lx86_64)
           libz         Compression Library (libz, -lz)

     Local, OS-specific additions might be found in the file
     mdoc.local; look for strings named `str-Lb-XXX'.  `XXX'
     then denotes the keyword to be used with the `.Lb' macro.

     In the LIBRARY section an `.Lb' command causes a line
     break before and after its arguments are printed.

   Literals
     The `.Li' literal macro may be used for special charac-
     ters, variable constants, etc. - anything which should be
     displayed as it would be typed.

           Usage: .Li <argument> ...

                    .Li \en          \n
                    .Li M1 M2 M3 ;   M1 M2 M3;
                    .Li cntrl-D ) ,  cntrl-D),
                    .Li 1024 ...     1024 ...

     The default width is 16n.

   Names
     The `.Nm' macro is used for the document title or subject
     name.  It has the peculiarity of remembering the first
     argument it was called with, which should always be the
     subject name of the page.  When called without arguments,
     `.Nm' regurgitates this initial name for the sole purpose
     of making less work for the author.  Note: A section two
     or three document function name is addressed with the
     `.Nm' in the NAME section, and with `.Fn' in the SYNOPSIS
     and remaining sections.  For interactive commands, such as
     the `while' command keyword in csh(1), the `.Ic' macro
     should be used.  While `.Ic' is nearly identical to `.Nm',
     it can not recall the first argument it was invoked with.

           Usage: .Nm [<argument>] ...

                    .Nm groff_mdoc  groff_mdoc
                    .Nm \-mdoc      -mdoc
                    .Nm foo ) ) ,   foo)),
                    .Nm :           groff_mdoc:

     The default width is 10n.

   Options
     The `.Op' macro places option brackets around any remain-
     ing arguments on the command line, and places any trailing
     punctuation outside the brackets.  The macros `.Oo' and
     `.Oc' (which produce an opening and a closing option
     bracket respectively) may be used across one or more lines
     or to specify the exact position of the closing parenthe-
     sis.

           Usage: .Op [<option>] ...

                    .Op                                []
                    .Op Fl k                           [-k]
                    .Op Fl k ) .                       [-k]).
                    .Op Fl k Ar kookfile               [-k
                                                       kookfile]
                    .Op Fl k Ar kookfile ,             [-k
                                                       kookfile],
                    .Op Ar objfil Op Ar corfil         [objfil
                                                       [corfil]]
                    .Op Fl c Ar objfil Op Ar corfil ,  [-c
                                                       objfil
                                                       [corfil]],
                    .Op word1 word2                    [word1
                                                       word2]
                    .Li .Op Oo Ao option Ac Oc ...     .Op
                                                       [<option>]
                                                       ...

     Here a typical example of the `.Oo' and `.Oc' macros:

           .Oo
           .Op Fl k Ar kilobytes
           .Op Fl i Ar interval
           .Op Fl c Ar count
           .Oc

     Produces:

           [[-k kilobytes] [-i interval] [-c count]]

     The default width values of `.Op' and `.Oo' are 14n and
     10n, respectively.

   Pathnames
     The `.Pa' macro formats path or file names.  If called
     without arguments, the `~' string is output, which repre-
     sents the current user's home directory.

           Usage: .Pa [<pathname>] ...

                    .Pa                    ~
                    .Pa /usr/share         /usr/share
                    .Pa /tmp/fooXXXXX ) .  /tmp/fooXXXXX).

     The default width is 32n.

   Standards
     The `.St' macro replaces standard abbreviations with their
     formal names.

           Usage: .St <abbreviation> ...

     Available pairs for ``Abbreviation/Formal Name'' are:

     ANSI/ISO C

           -ansiC          ANSI X3.159-1989 (``ANSI C89'')
           -ansiC-89       ANSI X3.159-1989 (``ANSI C89'')
           -isoC           ISO/IEC 9899:1990 (``ISO C90'')
           -isoC-90        ISO/IEC 9899:1990 (``ISO C90'')
           -isoC-99        ISO/IEC 9899:1999 (``ISO C99'')

     POSIX Part 1: System API

           -iso9945-1-90   ISO/IEC 9945-1:1990 (``POSIX.1'')
           -iso9945-1-96   ISO/IEC 9945-1:1996 (``POSIX.1'')
           -p1003.1        IEEE Std 1003.1 (``POSIX.1'')
           -p1003.1-88     IEEE Std 1003.1-1988 (``POSIX.1'')
           -p1003.1-90     ISO/IEC 9945-1:1990 (``POSIX.1'')
           -p1003.1-96     ISO/IEC 9945-1:1996 (``POSIX.1'')
           -p1003.1b-93    IEEE Std 1003.1b-1993 (``POSIX.1'')
           -p1003.1c-95    IEEE Std 1003.1c-1995 (``POSIX.1'')
           -p1003.1g-2000  IEEE Std 1003.1g-2000 (``POSIX.1'')
           -p1003.1i-95    IEEE Std 1003.1i-1995 (``POSIX.1'')
           -p1003.1-2001   IEEE Std 1003.1-2001 (``POSIX.1'')
           -p1003.1-2004   IEEE Std 1003.1-2004 (``POSIX.1'')

     POSIX Part 2: Shell and Utilities

           -iso9945-2-93   ISO/IEC 9945-2:1993 (``POSIX.2'')
           -p1003.2        IEEE Std 1003.2 (``POSIX.2'')
           -p1003.2-92     IEEE Std 1003.2-1992 (``POSIX.2'')
           -p1003.2a-92    IEEE Std 1003.2a-1992 (``POSIX.2'')

     X/Open

           -susv2          Version 2 of the Single UNIX
                           Specification (``SUSv2'')
           -susv3
           -svid4          System V Interface Definition,
                           Fourth Edition (``SVID4'')
           -xbd5           X/Open System Interface Definitions
                           Issue 5 (``XBD5'')
           -xcu5           X/Open Commands and Utilities
                           Issue 5 (``XCU5'')
           -xcurses4.2     X/Open Curses Issue 4, Version 2
                           (``XCURSES4.2'')
           -xns5           X/Open Networking Services Issue 5
                           (``XNS5'')
           -xns5.2         X/Open Networking Services Issue 5.2
                           (``XNS5.2'')
           -xpg3           X/Open Portability Guide Issue 3
                           (``XPG3'')
           -xpg4           X/Open Portability Guide Issue 4
                           (``XPG4'')
           -xpg4.2         X/Open Portability Guide Issue 4,
                           Version 2 (``XPG4.2'')
           -xsh5           X/Open System Interfaces and Headers
                           Issue 5 (``XSH5'')

     Miscellaneous

           -ieee754        IEEE Std 754-1985
           -iso8802-3      ISO/IEC 8802-3:1989

   Variable Types
     The `.Vt' macro may be used whenever a type is referenced.
     In the SYNOPSIS section, it causes a line break (useful
     for old style variable declarations).

           Usage: .Vt <type> ...

                    .Vt extern char *optarg ;  extern char
                                               *optarg;
                    .Vt FILE *                 FILE *

   Variables
     Generic variable reference.

           Usage: .Va <variable> ...

                    .Va count             count
                    .Va settimer ,        settimer,
                    .Va "int *prt" ) :    int *prt):
                    .Va "char s" ] ) ) ,  char s])),

     The default width is 12n.

   Manual Page Cross References
     The `.Xr' macro expects the first argument to be a manual
     page name.  The optional second argument, if a string
     (defining the manual section), is put into parentheses.

           Usage: .Xr <man page name> [<section>] ...

                    .Xr mdoc        mdoc
                    .Xr mdoc ,      mdoc,
                    .Xr mdoc 7      mdoc(7)
                    .Xr xinit 1x ;  xinit(1x);

     The default width is 10n.

GENERAL TEXT DOMAIN
   AT&T Macro
           Usage: .At [<version>] ...

                    .At       AT&T UNIX
                    .At v6 .  Version 6 AT&T UNIX.

     The following values for <version> are possible:

           32v, v1, v2, v3, v4, v5, v6, v7, V, V.1, V.2, V.3,
           V.4

   BSD Macro
           Usage: .Bx {-alpha | -beta | -devel} ...
                  .Bx [<version> [<release>]] ...

                    .Bx         BSD
                    .Bx 4.3 .   4.3BSD.
                    .Bx -devel  BSD (currently under
                                development)

     <version> will be prepended to the string `BSD'.  The fol-
     lowing values for <release> are possible:

           Reno, reno, Tahoe, tahoe, Lite, lite, Lite2, lite2

   NetBSD Macro
           Usage: .Nx [<version>] ...

                    .Nx        NetBSD
                    .Nx 1.4 .  NetBSD 1.4.

     For possible values of <version> see the description of
     the `.Os' command above in section TITLE MACROS.

   FreeBSD Macro
           Usage: .Fx [<version>] ...

                    .Fx        FreeBSD
                    .Fx 2.2 .  FreeBSD 2.2.

     For possible values of <version> see the description of
     the `.Os' command above in section TITLE MACROS.

   DragonFly Macro
           Usage: .Dx [<version>] ...

                    .Dx
                    .Dx 1.4 .

     For possible values of <version> see the description of
     the `.Os' command above in section TITLE MACROS.

   OpenBSD Macro
           Usage: .Ox [<version>] ...

                    .Ox 1.0  OpenBSD 1.0

   BSD/OS Macro
           Usage: .Bsx [<version>] ...

                    .Bsx 1.0  BSD/OS 1.0

   UNIX Macro
           Usage: .Ux ...

                    .Ux  UNIX

   Emphasis Macro
     Text may be stressed or emphasized with the `.Em' macro.
     The usual font for emphasis is italic.

           Usage: .Em <argument> ...

                    .Em does not          does not
                    .Em exceed 1024 .     exceed 1024.
                    .Em vide infra ) ) ,  vide infra)),

     The default width is 10n.

   Font Mode
     The `.Bf' font mode must be ended with the `.Ef' macro
     (the latter takes no arguments).  Font modes may be nested
     within other font modes.

     `.Bf' has the following syntax:

           .Bf <font mode>

     <font mode> must be one of the following three types:

           Em | -emphasis  Same as if the `.Em' macro was used
                           for the entire block of text.
           Li | -literal   Same as if the `.Li' macro was used
                           for the entire block of text.
           Sy | -symbolic  Same as if the `.Sy' macro was used
                           for the entire block of text.

     Both macros are neither callable nor parsed.

   Enclosure and Quoting Macros
     The concept of enclosure is similar to quoting.  The
     object being to enclose one or more strings between a pair
     of characters like quotes or parentheses.  The terms quot-
     ing and enclosure are used interchangeably throughout this
     document.  Most of the one-line enclosure macros end in
     small letter `q' to give a hint of quoting, but there are
     a few irregularities.  For each enclosure macro there is
     also a pair of open and close macros which end in small
     letters `o' and `c' respectively.

         Quote   Open    Close  Function                  Result
         .Aq     .Ao     .Ac    Angle Bracket Enclosure   <string>
         .Bq     .Bo     .Bc    Bracket Enclosure         [string]
         .Brq    .Bro    .Brc   Brace Enclosure           {string}
         .Dq     .Do     .Dc    Double Quote              ``string''
         .Eq     .Eo     .Ec    Enclose String (in XX)    XXstringXX
         .Pq     .Po     .Pc    Parenthesis Enclosure     (string)
         .Ql                    Quoted Literal            `string' or string
         .Qq     .Qo     .Qc    Straight Double Quote     "string"
         .Sq     .So     .Sc    Single Quote              `string'

     All macros ending with `q' and `o' have a default width
     value of 12n.

     .Eo, .Ec  These macros expect the first argument to be the
               opening and closing strings respectively.

     .Es, .En  Due to the nine-argument limit in the original
               troff program two other macros have been imple-
               mented which are now rather obsolete: `.Es'
               takes the first and second parameter as the left
               and right enclosure string, which are then used
               to enclose the arguments of `.En'.  The default
               width value is 12n for both macros.

     .Eq       The first and second arguments of this macro are
               the opening and closing strings respectively,
               followed by the arguments to be enclosed.

     .Ql       The quoted literal macro behaves differently in
               troff and nroff mode.  If formatted with nroff,
               a quoted literal is always quoted.  If formatted
               with troff, an item is only quoted if the width
               of the item is less than three constant width
               characters.  This is to make short strings more
               visible where the font change to literal (con-
               stant width) is less noticeable.

               The default width is 16n.

     .Pf       The prefix macro suppresses the whitespace
               between its first and second argument:

                     .Pf ( Fa name2  (name2

               The default width is 12n.

               The `.Ns' macro (see below) performs the analo-
               gous suffix function.

     .Ap       The `.Ap' macro inserts an apostrophe and exits
               any special text modes, continuing in `.No'
               mode.

     Examples of quoting:

           .Aq                      <>
           .Aq Pa ctype.h ) ,       <ctype.h>),
           .Bq                      []
           .Bq Em Greek , French .  [Greek, French].
           .Dq                      ``''
           .Dq string abc .         ``string abc''.
           .Dq ^[A-Z]             ``^[A-Z]''
           .Ql man mdoc             `man mdoc'
           .Qq                      ""
           .Qq string ) ,           "string"),
           .Qq string Ns ),         "string),"
           .Sq                      `'
           .Sq string               `string'
           .Em or Ap ing            or'ing

     For a good example of nested enclosure macros, see the
     `.Op' option macro.  It was created from the same underly-
     ing enclosure macros as those presented in the list above.
     The `.Xo' and `.Xc' extended argument list macros are dis-
     cussed below.

   No-Op or Normal Text Macro
     The `.No' macro can be used in a macro command line for
     parameters which should not be formatted.  Be careful to
     add `\&' to the word `No' if you really want that English
     word (and not the macro) as a parameter.

           Usage: .No <argument> ...

                    .No test Ta with Ta tabs  test     with     tabs

     The default width is 12n.

   No-Space Macro
     The `.Ns' macro suppresses insertion of a space between
     the current position and its first parameter.  For exam-
     ple, it is useful for old style argument lists where there
     is no space between the flag and argument:

           Usage: ... <argument> Ns [<argument>] ...
                  .Ns <argument> ...

                    .Op Fl I Ns Ar directory  [-Idirectory]

     Note: The `.Ns' macro always invokes the `.No' macro after
     eliminating the space unless another macro name follows
     it.  If used as a command (i.e., the second form above in
     the `Usage' line), `.Ns' is identical to `.No'.

   Section Cross References
     The `.Sx' macro designates a reference to a section header
     within the same document.

           Usage: .Sx <section reference> ...

                    .Sx FILES  FILES

     The default width is 16n.

   Symbolics
     The symbolic emphasis macro is generally a boldface macro
     in either the symbolic sense or the traditional English
     usage.

           Usage: .Sy <symbol> ...

                    .Sy Important Notice  Important Notice

     The default width is 6n.

   Mathematical Symbols
     Use this macro for mathematical symbols and similar
     things.

           Usage: .Ms <math symbol> ...

                    .Ms sigma  sigma

     The default width is 6n.

   References and Citations
     The following macros make a modest attempt to handle ref-
     erences.  At best, the macros make it convenient to manu-
     ally drop in a subset of refer(1) style references.

           .Rs     Reference start (does not take arguments).
                   Causes a line break in the SEE ALSO section
                   and begins collection of reference informa-
                   tion until the reference end macro is read.
           .Re     Reference end (does not take arguments).
                   The reference is printed.
           .%A     Reference author name; one name per invoca-
                   tion.
           .%B     Book title.
           .%C     City/place (not implemented yet).
           .%D     Date.
           .%I     Issuer/publisher name.
           .%J     Journal name.
           .%N     Issue number.
           .%O     Optional information.
           .%P     Page number.
           .%Q     Corporate or foreign author.
           .%R     Report name.
           .%T     Title of article.
           .%V     Volume.

     Macros beginning with `%' are not callable but accept mul-
     tiple arguments in the usual way.  Only the `.Tn' macro is
     handled properly as a parameter; other macros will cause
     strange output.  `.%B' and `.%T' can be used outside of
     the `.Rs/.Re' environment.

     Example:

           .Rs
           .%A "Matthew Bar"
           .%A "John Foo"
           .%T "Implementation Notes on foobar(1)"
           .%R "Technical Report ABC-DE-12-345"
           .%Q "Drofnats College, Nowhere"
           .%D "April 1991"
           .Re

     produces

           Matthew Bar and John Foo, Implementation Notes on
           foobar(1), Technical Report ABC-DE-12-345, Drofnats
           College, Nowhere, April 1991.

   Trade Names (or Acronyms and Type Names)
     The trade name macro prints its arguments in a smaller
     font.  Its intended use is to imitate a small caps fonts
     for uppercase acronyms.

           Usage: .Tn <symbol> ...

                    .Tn DEC    DEC
                    .Tn ASCII  ASCII

     The default width is 10n.

   Extended Arguments
     The .Xo and .Xc macros allow one to extend an argument
     list on a macro boundary for the `.It' macro (see below).
     Note that .Xo and .Xc are implemented similarly to all
     other macros opening and closing an enclosure (without
     inserting characters, of course).  This means that the
     following is true for those macros also.

     Here is an example of `.Xo' using the space mode macro to
     turn spacing off:

           .Sm off
           .It Xo Sy I Ar operation
           .No \en Ar count No \en
           .Xc
           .Sm on

     produces

           Ioperation\ncount\n

     Another one:

           .Sm off
           .It Cm S No / Ar old_pattern Xo
           .No / Ar new_pattern
           .No / Op Cm g
           .Xc
           .Sm on

     produces

           S/old_pattern/new_pattern/[g]

     Another example of `.Xo' and enclosure macros: Test the
     value of a variable.

           .It Xo
           .Ic .ifndef
           .Oo \&! Oc Ns Ar variable Oo
           .Ar operator variable ...
           .Oc Xc

     produces

           .ifndef [!]variable [operator variable ...]

PAGE STRUCTURE DOMAIN
   Section Headers
     The following `.Sh' section header macros are required in
     every man page.  The remaining section headers are recom-
     mended at the discretion of the author writing the manual
     page.  The `.Sh' macro is parsed but not generally
     callable.  It can be used as an argument in a call to
     `.Sh' only; it then reactivates the default font for
     `.Sh'.

     The default width is 8n.

     .Sh NAME           The `.Sh NAME' macro is mandatory.  If
                        not specified, headers, footers and
                        page layout defaults will not be set
                        and things will be rather unpleasant.
                        The NAME section consists of at least
                        three items.  The first is the `.Nm'
                        name macro naming the subject of the
                        man page.  The second is the name
                        description macro, `.Nd', which sepa-
                        rates the subject name from the third
                        item, which is the description.  The
                        description should be the most terse
                        and lucid possible, as the space avail-
                        able is small.

                        `.Nd' first prints `-', then all its
                        arguments.

     .Sh LIBRARY        This section is for section two and
                        three function calls.  It should con-
                        sist of a single `.Lb' macro call; see
                        Library Names.

     .Sh SYNOPSIS       The SYNOPSIS section describes the typ-
                        ical usage of the subject of a man
                        page.  The macros required are either
                        `.Nm', `.Cd', or `.Fn' (and possibly
                        `.Fo', `.Fc', `.Fd', and `.Ft').  The
                        function name macro `.Fn' is required
                        for manual page sections 2 and 3; the
                        command and general name macro `.Nm' is
                        required for sections 1, 5, 6, 7,
                        and 8.  Section 4 manuals require a
                        `.Nm', `.Fd' or a `.Cd' configuration
                        device usage macro.  Several other
                        macros may be necessary to produce the
                        synopsis line as shown below:

                              cat [-benstuv] [-] file ...

                        The following macros were used:

                              .Nm cat
                              .Op Fl benstuv
                              .Op Fl
                              .Ar

     .Sh DESCRIPTION    In most cases the first text in the
                        DESCRIPTION section is a brief para-
                        graph on the command, function or file,
                        followed by a lexical list of options
                        and respective explanations.  To create
                        such a list, the `.Bl' (begin list),
                        `.It' (list item) and `.El' (end list)
                        macros are used (see Lists and Columns
                        below).

     .Sh IMPLEMENTATION NOTES
                        Implementation specific information
                        should be placed here.

     .Sh RETURN VALUES  Sections 2, 3 and 9 function return
                        values should go here.  The `.Rv' macro
                        may be used to generate text for use in
                        the RETURN VALUES section for most sec-
                        tion 2 and 3 library functions; see
                        Return Values.

     The following `.Sh' section headers are part of the pre-
     ferred manual page layout and must be used appropriately
     to maintain consistency.  They are listed in the order in
     which they would be used.

     .Sh ENVIRONMENT    The ENVIRONMENT section should reveal
                        any related environment variables and
                        clues to their behavior and/or usage.

     .Sh FILES          Files which are used or created by the
                        man page subject should be listed via
                        the `.Pa' macro in the FILES section.

     .Sh EXAMPLES       There are several ways to create exam-
                        ples.  See the EXAMPLES section below
                        for details.

     .Sh DIAGNOSTICS    Diagnostic messages from a command
                        should be placed in this section.  The
                        `.Ex' macro may be used to generate
                        text for use in the DIAGNOSTICS section
                        for most section 1, 6 and 8 commands;
                        see Exit Status.

     .Sh COMPATIBILITY  Known compatibility issues (e.g. depre-
                        cated options or parameters) should be
                        listed here.

     .Sh ERRORS         Specific error handling, especially
                        from library functions (man page sec-
                        tions 2, 3, and 9) should go here.  The
                        `.Er' macro is used to specify an error
                        (errno).

     .Sh SEE ALSO       References to other material on the man
                        page topic and cross references to
                        other relevant man pages should be
                        placed in the SEE ALSO section.  Cross
                        references are specified using the
                        `.Xr' macro.  Currently refer(1) style
                        references are not accommodated.

                        It is recommended that the cross refer-
                        ences are sorted on the section number,
                        then alphabetically on the names within
                        a section, and placed in that order and
                        comma separated.  Example:

                        ls(1), ps(1), group(5), passwd(5)

     .Sh STANDARDS      If the command, library function or
                        file adheres to a specific implementa-
                        tion such as IEEE Std 1003.2
                        (``POSIX.2'') or ANSI X3.159-1989
                        (``ANSI C89'') this should be noted
                        here.  If the command does not adhere
                        to any standard, its history should be
                        noted in the HISTORY section.

     .Sh HISTORY        Any command which does not adhere to
                        any specific standards should be out-
                        lined historically in this section.

     .Sh AUTHORS        Credits should be placed here.  Use the
                        `.An' macro for names and the `.Aq'
                        macro for e-mail addresses within
                        optional contact information.  Explic-
                        itly indicate whether the person
                        authored the initial manual page or the
                        software or whatever the person is
                        being credited for.

     .Sh BUGS           Blatant problems with the topic go
                        here.

     User-specified `.Sh' sections may be added; for example,
     this section was set with:

                    .Sh "PAGE STRUCTURE DOMAIN"

   Subsection Headers
     Subsection headers have exactly the same syntax as section
     headers: `.Ss' is parsed but not generally callable.  It
     can be used as an argument in a call to `.Ss' only; it
     then reactivates the default font for `.Ss'.

     The default width is 8n.

   Paragraphs and Line Spacing
     .Pp  The `.Pp' paragraph command may be used to specify a
          line space where necessary.  The macro is not neces-
          sary after a `.Sh' or `.Ss' macro or before a `.Bl'
          or `.Bd' macro (which both assert a vertical distance
          unless the -compact flag is given).

          The macro is neither callable nor parsed and takes no
          arguments; an alternative name is `.Lp'.

   Keeps
     The only keep that is implemented at this time is for
     words.  The macros are `.Bk' (begin keep) and `.Ek' (end
     keep).  The only option that `.Bk' accepts currently is
     -words (this is also the default if no option is given)
     which is useful for preventing line breaks in the middle
     of options.  In the example for the make command line
     arguments (see What's in a Name), the keep prevented nroff
     from placing up the flag and the argument on separate
     lines.

     Both macros are neither callable nor parsed.

     More work needs to be done with the keep macros; specifi-
     cally, a -line option should be added.

   Examples and Displays
     There are seven types of displays.

     .D1  (This is D-one.)  Display one line of indented text.
          This macro is parsed but not callable.

                -ldghfstru

          The above was produced by: .D1 Fl ldghfstru.

     .Dl  (This is D-ell.)  Display one line of indented
          literal text.  The `.Dl' example macro has been used
          throughout this file.  It allows the indentation
          (display) of one line of text.  Its default font is
          set to constant width (literal).  `.Dl' is parsed but
          not callable.

                % ls -ldg /usr/local/bin

          The above was produced by: .Dl % ls \-ldg
          /usr/local/bin.

     .Bd  Begin display.  The `.Bd' display must be ended with
          the `.Ed' macro.  It has the following syntax:

                .Bd {-literal | -filled | -unfilled | -ragged |
                     -centered} [-offset <string>] [-file <file
                     name>] [-compact]

          -ragged            Fill, but do not adjust the right
                             margin (only left-justify).
          -centered          Center lines between the current
                             left and right margin.  Note that
                             each single line is centered.
          -unfilled          Do not fill; display a block of
                             text as typed, using line breaks
                             as specified by the user.  This
                             can produce overlong lines without
                             warning messages.
          -filled            Display a filled block.  The block
                             of text is formatted (i.e., the
                             text is justified on both the left
                             and right side).
          -literal           Display block with literal font
                             (usually fixed-width).  Useful for
                             source code or simple tabbed or
                             spaced text.
          -file <file name>  The file whose name follows the
                             -file flag is read and displayed
                             before any data enclosed with
                             `.Bd' and `.Ed', using the
                             selected display type.  Any
                             troff/-mdoc commands in the file
                             will be processed.
          -offset <string>   If -offset is specified with one
                             of the following strings, the
                             string is interpreted to indicate
                             the level of indentation for the
                             forthcoming block of text:

                             left        Align block on the
                                         current left margin;
                                         this is the default
                                         mode of `.Bd'.
                             center      Supposedly center the
                                         block.  At this time
                                         unfortunately, the
                                         block merely gets left
                                         aligned about an imag-
                                         inary center margin.
                             indent      Indent by one default
                                         indent value or tab.
                                         The default indent
                                         value is also used for
                                         the `.D1' and `.Dl'
                                         macros, so one is
                                         guaranteed the two
                                         types of displays will
                                         line up.  The indenta-
                                         tion value is normally
                                         set to 6n or about two
                                         thirds of an inch (six
                                         constant width charac-
                                         ters).
                             indent-two  Indent two times the
                                         default indent value.
                             right       This left aligns the
                                         block about two inches
                                         from the right side of
                                         the page.  This macro
                                         needs work and perhaps
                                         may never do the right
                                         thing within troff.

                             If <string> is a valid numeric
                             expression instead (with a scale
                             indicator other than `u'), use
                             that value for indentation.  The
                             most useful scale indicators are
                             `m' and `n', specifying the so-
                             called Em and En square.  This is
                             approximately the width of the
                             letters `m' and `n' respectively
                             of the current font (for nroff
                             output, both scale indicators give
                             the same values).  If <string>
                             isn't a numeric expression, it is
                             tested whether it is an -mdoc
                             macro name, and the default offset
                             value associated with this macro
                             is used.  Finally, if all tests
                             fail, the width of <string> (type-
                             set with a fixed-width font) is
                             taken as the offset.
          -compact           Suppress insertion of vertical
                             space before begin of display.

     .Ed  End display (takes no arguments).

   Lists and Columns
     There are several types of lists which may be initiated
     with the `.Bl' begin-list macro.  Items within the list
     are specified with the `.It' item macro, and each list
     must end with the `.El' macro.  Lists may be nested within
     themselves and within displays.  The use of columns inside
     of lists or lists inside of columns is unproven.

     In addition, several list attributes may be specified such
     as the width of a tag, the list offset, and compactness
     (blank lines between items allowed or disallowed).  Most
     of this document has been formatted with a tag style list
     (-tag).

     It has the following syntax forms:

           .Bl {-hang | -ohang | -tag | -diag | -inset} [-width
                <string>] [-offset <string>] [-compact]
           .Bl -column [-offset <string>] <string1> <string2>
                ...
           .Bl {-item | -enum [-nested] | -bullet | -hyphen |
                -dash} [-offset <string>] [-compact]

     And now a detailed description of the list types.

     -bullet  A bullet list.

                    .Bl -bullet -offset indent -compact
                    .It
                    Bullet one goes here.
                    .It
                    Bullet two here.
                    .El

              Produces:

                       Bullet one goes here.
                       Bullet two here.

     -dash (or -hyphen)
              A dash list.

                    .Bl -dash -offset indent -compact
                    .It
                    Dash one goes here.
                    .It
                    Dash two here.
                    .El

              Produces:

                    -   Dash one goes here.
                    -   Dash two here.

     -enum    An enumerated list.

                    .Bl -enum -offset indent -compact
                    .It
                    Item one goes here.
                    .It
                    And item two here.
                    .El

              The result:

                    1.   Item one goes here.
                    2.   And item two here.

              If you want to nest enumerated lists, use the
              -nested flag (starting with the second-level
              list):

                    .Bl -enum -offset indent -compact
                    .It
                    Item one goes here
                    .Bl -enum -nested -compact
                    .It
                    Item two goes here.
                    .It
                    And item three here.
                    .El
                    .It
                    And item four here.
                    .El

              Result:

                    1.   Item one goes here.
                         1.1.   Item two goes here.
                         1.2.   And item three here.
                    2.   And item four here.

     -item    A list of type -item without list markers.

                    .Bl -item -offset indent
                    .It
                    Item one goes here.
                    Item one goes here.
                    Item one goes here.
                    .It
                    Item two here.
                    Item two here.
                    Item two here.
                    .El

              Produces:

                    Item one goes here.  Item one goes here.
                    Item one goes here.

                    Item two here.  Item two here.  Item two
                    here.

     -tag     A list with tags.  Use -width to specify the tag
              width.

                    SL    sleep time of the process (seconds
                          blocked)
                    PAGEIN
                          number of disk I/O's resulting from
                          references by the process to pages
                          not loaded in core.
                    UID   numerical user-id of process owner
                    PPID  numerical id of parent of process
                          priority (non-positive when in non-
                          interruptible wait)

              The raw text:

                    .Bl -tag -width "PPID" -compact -offset indent
                    .It SL
                    sleep time of the process (seconds blocked)
                    .It PAGEIN
                    number of disk
                    .Tn I/O Ns 's
                    resulting from references by the process
                    to pages not loaded in core.
                    .It UID
                    numerical user-id of process owner
                    .It PPID
                    numerical id of parent of process priority
                    (non-positive when in non-interruptible wait)
                    .El

     -diag    Diag lists create section four diagnostic lists
              and are similar to inset lists except callable
              macros are ignored.  The -width flag is not mean-
              ingful in this context.

              Example:

                    .Bl -diag
                    .It You can't use Sy here.
                    The message says all.
                    .El

              produces

              You can't use Sy here.  The message says all.

     -hang    A list with hanging tags.

                    Hanged  labels appear similar to tagged
                            lists when the label is smaller
                            than the label width.

                    Longer hanged list labels blend into the
                            paragraph unlike tagged paragraph
                            labels.

              And the unformatted text which created it:

                    .Bl -hang -offset indent
                    .It Em Hanged
                    labels appear similar to tagged lists when the
                    label is smaller than the label width.
                    .It Em Longer hanged list labels
                    blend into the paragraph unlike
                    tagged paragraph labels.
                    .El

     -ohang   Lists with overhanging tags do not use indenta-
              tion for the items; tags are written to a sepa-
              rate line.

                    SL
                    sleep time of the process (seconds blocked)

                    PAGEIN
                    number of disk I/O's resulting from refer-
                    ences by the process to pages not loaded in
                    core.

                    UID
                    numerical user-id of process owner

                    PPID
                    numerical id of parent of process priority
                    (non-positive when in non-interruptible
                    wait)

              The raw text:

                    .Bl -ohang -offset indent
                    .It Sy SL
                    sleep time of the process (seconds blocked)
                    .It Sy PAGEIN
                    number of disk
                    .Tn I/O Ns 's
                    resulting from references by the process
                    to pages not loaded in core.
                    .It Sy UID
                    numerical user-id of process owner
                    .It Sy PPID
                    numerical id of parent of process priority
                    (non-positive when in non-interruptible wait)
                    .El

     -inset   Here is an example of inset labels:

                    Tag The tagged list (also called a tagged
                    paragraph) is the most common type of list
                    used in the Berkeley manuals.  Use a -width
                    attribute as described below.

                    Diag Diag lists create section four diag-
                    nostic lists and are similar to inset lists
                    except callable macros are ignored.

                    Hang Hanged labels are a matter of taste.

                    Ohang Overhanging labels are nice when
                    space is constrained.

                    Inset Inset labels are useful for control-
                    ling blocks of paragraphs and are valuable
                    for converting -mdoc manuals to other for-
                    mats.

              Here is the source text which produced the above
              example:

                    .Bl -inset -offset indent
                    .It Em Tag
                    The tagged list (also called a tagged paragraph)
                    is the most common type of list used in the
                    Berkeley manuals.
                    .It Em Diag
                    Diag lists create section four diagnostic lists
                    and are similar to inset lists except callable
                    macros are ignored.
                    .It Em Hang
                    Hanged labels are a matter of taste.
                    .It Em Ohang
                    Overhanging labels are nice when space is constrained.
                    .It Em Inset
                    Inset labels are useful for controlling blocks of
                    paragraphs and are valuable for converting
                    .Nm -mdoc
                    manuals to other formats.
                    .El

     -column  This list type generates multiple columns.  The
              number of columns and the width of each column is
              determined by the arguments to the -column list,
              <string1>, <string2>, etc.  If <stringN> starts
              with a `.' (dot) immediately followed by a valid
              -mdoc macro name, interpret <stringN> and use the
              width of the result.  Otherwise, the width of
              <stringN> (typeset with a fixed-width font) is
              taken as the Nth column width.

              Each `.It' argument is parsed to make a row, each
              column within the row is a separate argument sep-
              arated by a tab or the `.Ta' macro.

              The table:

                    String    Nroff    Troff
                    <=        <=       <=
                    >=        >=       >=

              was produced by:

              .Bl -column -offset indent ".Sy String" ".Sy Nroff" ".Sy Troff"
              .It Sy String Ta Sy Nroff Ta Sy Troff
              .It Li <= Ta <= Ta \*(<=
              .It Li >= Ta >= Ta \*(>=
              .El

              Don't abuse this list type!  For more complicated
              cases it might be far better and easier to use
              tbl(1), the table preprocessor.

     Other keywords:

     -width <string>   If <string> starts with a `.' (dot)
                       immediately followed by a valid -mdoc
                       macro name, interpret <string> and use
                       the width of the result.  Almost all
                       lists in this document use this option.

                       Example:

                             .Bl -tag -width ".Fl test Ao Ar string Ac"
                             .It Fl test Ao Ar string Ac
                             This is a longer sentence to show how the
                             .Fl width
                             flag works in combination with a tag list.
                             .El

                       gives:

                       -test <string>  This is a longer sen-
                                       tence to show how the
                                       -width flag works in
                                       combination with a tag
                                       list.

                       (Note that the current state of -mdoc is
                       saved before <string> is interpreted;
                       afterwards, all variables are restored
                       again.  However, boxes (used for enclo-
                       sures) can't be saved in GNU troff(1);
                       as a consequence, arguments must always
                       be balanced to avoid nasty errors.  For
                       example, do not write `.Ao Ar string'
                       but `.Ao Ar string Xc' instead if you
                       really need only an opening angle
                       bracket.)

                       Otherwise, if <string> is a valid
                       numeric expression (with a scale
                       indicator other than `u'), use that
                       value for indentation.  The most useful
                       scale indicators are `m' and `n', speci-
                       fying the so-called Em and En square.
                       This is approximately the width of the
                       letters `m' and `n' respectively of the
                       current font (for nroff output, both
                       scale indicators give the same values).
                       If <string> isn't a numeric expression,
                       it is tested whether it is an -mdoc
                       macro name, and the default width value
                       associated with this macro is used.
                       Finally, if all tests fail, the width of
                       <string> (typeset with a fixed-width
                       font) is taken as the width.

                       If a width is not specified for the tag
                       list type, every time `.It' is invoked,
                       an attempt is made to determine an
                       appropriate width.  If the first argu-
                       ment to `.It' is a callable macro, the
                       default width for that macro will be
                       used; otherwise, the default width of
                       `.No' is used.

     -offset <string>  If <string> is indent, a default indent
                       value (normally set to 6n, similar to
                       the value used in `.Dl' or `.Bd') is
                       used.  If <string> is a valid numeric
                       expression instead (with a scale
                       indicator other than `u'), use that
                       value for indentation.  The most useful
                       scale indicators are `m' and `n', speci-
                       fying the so-called Em and En square.
                       This is approximately the width of the
                       letters `m' and `n' respectively of the
                       current font (for nroff output, both
                       scale indicators give the same values).
                       If <string> isn't a numeric expression,
                       it is tested whether it is an -mdoc
                       macro name, and the default offset value
                       associated with this macro is used.
                       Finally, if all tests fail, the width of
                       <string> (typeset with a fixed-width
                       font) is taken as the offset.

     -compact          Suppress insertion of vertical space
                       before the list and between list items.

MISCELLANEOUS MACROS
     Here a list of the remaining macros which do not fit well
     into one of the above sections.  We couldn't find real
     examples for the following macros: `.Me' and `.Ot'.  They
     are documented here for completeness - if you know how to
     use them properly please send a mail to bug-groff@gnu.org
     (including an example).

     .Bt  prints

                is currently in beta test.

          It is neither callable nor parsed and takes no argu-
          ments.

     .Fr

                Usage: .Fr <function return value> ...

          Don't use this macro.  It allows a break right before
          the return value (usually a single digit) which is
          bad typographical behaviour.  Use `\~' to tie the
          return value to the previous word.

     .Hf  Use this macro to include a (header) file literally.
          It first prints `File:' followed by the file name,
          then the contents of <file>.

                Usage: .Hf <file>

          It is neither callable nor parsed.

     .Lk  To be written.

     .Me  Exact usage unknown.  The documentation in the -mdoc
          source file describes it as a macro for ``menu
          entries''.

          Its default width is 6n.

     .Mt  To be written.

     .Ot  Exact usage unknown.  The documentation in the -mdoc
          source file describes it as ``old function type
          (fortran)''.

     .Sm  Activate (toggle) space mode.

                Usage: .Sm [on | off] ...

          If space mode is off, no spaces between macro argu-
          ments are inserted.  If called without a parameter
          (or if the next parameter is neither `on' nor `off',
          `.Sm' toggles space mode.

     .Ud  prints

                currently under development.

          It is neither callable nor parsed and takes no argu-
          ments.

PREDEFINED STRINGS
     The following strings are predefined:

           String    Nroff       Troff     Meaning
           <=        <=          <=        less equal
           >=        >=          >=        greater equal
           Rq        ''          ''        right double quote
           Lq        ``          ``        left double quote
           ua        ^           ^         upwards arrow
           aa                            acute accent
           ga        `           `         grave accent
           q         "           "         straight double
                                                                    quote
           Pi        pi          pi        greek pi
           Ne        !=          !=        not equal
           Le        <=          <=        less equal
           Ge        >=          >=        greater equal
           Lt        <           <         less than
           Gt        >           >         greater than
           Pm        +-                   plus minus
           If        infinity    infinity  infinity
           Am        &           &         ampersand
           Na        NaN         NaN       not a number
           Ba        |           |         vertical bar

     The names of the columns Nroff and Troff are a bit mis-
     leading; Nroff shows the ASCII representation, while Troff
     gives the best glyph form available.  For example, a Uni-
     code enabled TTY-device will have proper glyph representa-
     tions for all strings, whereas the enhancement for a
     Latin1 TTY-device is only the plus-minus sign.

     String names which consist of two characters can be writ-
     ten as `\*(xx'; string names which consist of one charac-
     ter can be written as `\*x'.  A generic syntax for a
     string name of any length is `\*[xxx]' (this is a GNU
     troff(1) extension).

DIAGNOSTICS
     The debugging macro `.Db' available in previous versions
     of -mdoc has been removed since GNU troff(1) provides bet-
     ter facilities to check parameters; additionally, many
     error and warning messages have been added to this macro
     package, making it both more robust and verbose.

     The only remaining debugging macro is `.Rd' which yields a
     register dump of all global registers and strings.  A nor-
     mal user will never need it.

FORMATTING WITH GROFF, TROFF, AND NROFF
     By default, the package inhibits page breaks, headers, and
     footers if displayed with a TTY device like `latin1' or
     `unicode', to make the manual more efficient for viewing
     on-line.  This behaviour can be changed (e.g. to create a
     hardcopy of the TTY output) by setting the register `cR'
     to zero while calling groff(1), resulting in multiple
     pages instead of a single, very long page:

           groff -Tlatin1 -rcR=0 -mdoc foo.man > foo.txt

     For double-sided printing, set register `D' to 1:

           groff -Tps -rD1 -mdoc foo.man > foo.ps

     To change the document font size to 11pt or 12pt, set reg-
     ister `S' accordingly:

           groff -Tdvi -rS11 -mdoc foo.man > foo.dvi

     Register `S' is ignored for TTY devices.

     The line and title length can be changed by setting the
     registers `LL' and `LT', respectively:

           groff -Tutf8 -rLL=100n -rLT=100n -mdoc foo.man |
           less

     If not set, both registers default to 78n for TTY devices
     and 6.5i otherwise.

FILES
     doc.tmac          The main manual macro package.
     mdoc.tmac         A wrapper file to call doc.tmac.
     mdoc/doc-common   Common strings, definitions, stuff
                       related typographic output.
     mdoc/doc-nroff    Definitions used for a TTY output
                       device.
     mdoc/doc-ditroff  Definitions used for all other devices.
     mdoc.local        Local additions and customizations.
     andoc.tmac        Use this file if you don't know whether
                       the -mdoc or the -man package should be
                       used.  Multiple man pages (in either
                       format) can be handled.

SEE ALSO
     groff(1), man(1), troff(1), groff_man(7)

BUGS
     Section 3f has not been added to the header routines.

     `.Nm' font should be changed in NAME section.

     `.Fn' needs to have a check to prevent splitting up if the
     line length is too short.  Occasionally it separates the
     last parenthesis, and sometimes looks ridiculous if a line
     is in fill mode.

     The list and display macros do not do any keeps and cer-
     tainly should be able to.

BSD                             January 5, 2006                            BSD
