MDOC.SAMPLES(7) BSD Reference Manual MDOC.SAMPLES(7)
NAME
mdoc.sample - writing manual pages with -mdoc macro package
SYNOPSIS
man mdoc.sample
DESCRIPTION
A tutorial sampler for writing BSD UNIX manual pages with the -mdoc macro
package, a content-based formatting package for troff(1). Its predeces-
sor, the -man(7) package, addressed page structure leaving the manipula-
tion of fonts and other typesetting details to the individual author.
The -mdoc package allows the author to ignore font considerations by us-
ing macros to label pieces of text according to content. In the context
of manual pages, examples of content are a command name, a file pathname
or a cross reference to another manual page; these items have value for
both the author and the future user of the manual page. It is hoped the
consistency gained across the manual set will provide easier translation
to future documentation tools.
Through out the UNIX manual pages, a manual entry is simply referred to
as a man page, regardless of actual length and without sexist intention.
TROFF IDIOSYNCRASIES
The -mdoc package attempts to simplify the process of writing a man page.
Theoretically, one should not have to learn the dirty details of 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 troff(1), a macro is called by placing a `.' (dot character) at
the beginning of a line followed by the two character name for the macro.
Arguments may follow the macro separated by spaces. It is the dot char-
acter at the beginning of the line which causes troff(1) to interpret the
next two characters as a macro name. To place a `.' (dot character) at
the beginning of a line in some context other than a macro macro, precede
the `.' (dot) with a `\&'.
In general, troff(1) macros accept up to nine arguments, any extra argu-
ments are ignored. Most macros in -mdoc accept nine arguments and, in
limited cases, arguments may be continued or extended on the next line
(See Extensions - macro `.Xo' and `.Xc'). A few macros handle quoted ar-
guments (see Passing Space Characters in an Argument below). Many -mdoc
macros may be given the name of another macro as an argument. In this
case the argument, although the name of a macro, is not preceded by a `.'
(dot), and is called when the argument is processed. It is in this man-
ner that some macros are nested; for example the option macro, `.Op', may
call the flag and argument macros, `.Fl' and `.Ar', to specify an option-
al flag with an argument:
[-s bytes] is produced by .Op Fl s Ar bytes
To prevent a two character 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' were not interpreted as macros. Details
on callable macros are presented in the sections CONTENT MACROS and PAGE
LAYOUT MACROS.
Passing Space Characters in an Argument
Sometimes it is desirable to give as one argument a string containing one
or more blank space characters. This may be necessary to defeat the nine
argument limit or to specify arguments to macros which expect particular
arrangement of items in the argument list. For example, the function
macro `.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 function 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 contains an embedded space. Unfortunately, the most convenient way
of passing such a space between quotes was too expensive to implement for
all the macros. It is however, implemented for the following macros which
need it the most:
Cd Configuration declaration (section 4 SYNOPSIS)
Bl Begin list (for the width specifier).
Em Emphasized text.
Fn Functions (sections two and four).
It List items.
Li Literal text.
Sy Symbolic text.
%B Book titles.
%J Journal names.
%O Optional notes for a reference.
%R Report title (in a reference).
%T Title of article in a book or journal.
One way of passing a string containing 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 separated
pieces as one would expect. The method is useful for strings which are
not expected to overlap a line boundary. 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 `\' or quotes were omitted, `.Fn' would see three arguments and
the result would be:
fetch(char, *str)
For an example of what happens when the parameter list overlaps a newline
boundary, see the BUGS section.
Trailing Blank Space Characters
Troff can be confused by blank space characters at the end of a line. It
is wise preventative measure to globally remove all blank spaces from
<blank-space><end-of-line> character sequences. Should the need arise to
force a blank character at the end of a line, it may be forced with an
unpaddable space and the `\&' escape character. For example,
`string\ \&'.
Escaping Special Characters
Special characters like the newline character `\n', are handled by re-
placing the `\' with `\e' (e.g. `\en') to preserve the backslash.
THE ANATOMY OF A MAN PAGE (Getting Started)
There are three basic groups of macros: specific header macros called on-
ly once at the very beginning of each manual page, page layout or struc-
ture macros which may be called many times, and content macros which also
may be called many times. The body of a man page is easily constructed
from a basic template found in the file:
.\" /usr/share/misc/mdoc.template :
.\" The following six lines are required.
.Dt DOCUMENT_TITLE [section number] [volume]
.Os OPERATING_SYSTEM [version/release]
.Dd Month day, year
.Sh NAME
.Sh SYNOPSIS
.Sh DESCRIPTION
.\" The following requests should be uncommented and
.\" used where appropriate. This next request is
.\" for sections 2 and 3 function return values only.
.\" .Sh RETURN VALUES
.\" This next request is for sections 1, 6, 7 & 8 only
.\" .Sh ENVIRONMENT
.\" .Sh FILES
.\" .Sh EXAMPLES
.\" This next request is for sections 1, 6, 7 & 8 only
.\" (command return values (to shell) and
.\" fprintf/stderr type diagnostics)
.\" .Sh DIAGNOSTICS
.\" The next request is for sections 2 and 3 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 macros (.Dt, .Dd, .Os); the docu-
ment or man page title (in upper case), the section of the manual the
page belongs to, the (document) date, and the operating system the man
page is derived from. These macros 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 mandatory. The headers are discussed
in PAGE LAYOUT MACROS, after presentation of CONTENT MACROS. Several con-
tent macros are used to demonstrate page layout macros; reading about
content macros before page layout macros is recommended.
TITLE MACROS
Three header macros designate the document title or manual page title,
the operating system, and the date of authorship. These macros are one
called once at the very beginning of the document and are used to con-
struct the headers and footers only.
.Dt DOCUMENT_TITLE section# [volume]
The document title is the subject of the man page and must be in
CAPITALS due to troff limitations. The section number may be
1, ..., 8, and if it is specified, the volume title may be omit-
ted. A volume title may be arbitrary or one of the following:
AMD UNIX Ancestral Manual Documents
SMM UNIX System Manager's Manual
URM UNIX Reference Manual
PRM UNIX Programmers's Manual
.Os operating_system release#
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, e.g. 4.3, 4.3+Tahoe, V.3,
V.4. Unrecognized arguments are displayed as given in the page
footer. For instance, for the footer on this page, the 4.4
Berkeley Distribution was produced by:
.Os BSD 4.4
.Dd month day, year
The date should be written formally:
January 25, 1989
CONTENT MACROS
What's in a name...
Content macro names are derived from the day to day informal language
used to describe commands, subroutines and related files. Slightly dif-
ferent variations of this language are used to describe the three differ-
ent aspects of writing a man page. First, there is the description of
-mdoc macro request usage. Second is the description of a UNIX command
with -mdoc macros and third, the description a command to a user in the
verbal 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:
.Va argument1 argument2 ... argument9
The `.Va' is a macro command or request, and anything following it is an
argument to be processed. In the second case, the description of a UNIX
command using the content macros is a bit more involved; a typical SYNOP-
SIS 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 arguments. The macros which formatted the
above example:
.Nm filter
.Op Fl flag
.Ar infile outfile
In the third case, discussion of commands and command syntax 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 maxjobs] [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 operand or file ar-
gument like target as well as an argument to a flag like variable:
.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=value
.Op Ar target ...
General Syntax
All content macros share a similar syntax with a few minor deviations:
`.Ar', `.Fl', `.Nm', and `.Pa' differ only when called without arguments;
`.Fn' and `.Xr' impose an order on their argument lists and the enclosure
and quoting macros have nesting limitations. All content macros are capa-
ble of handling punctuation. Any argument which may be tested for punc-
tuation and contains a member of the mathematical, logical or quotation
set:
{+,-,/,*,%,<,>,<=,>=,=,==,&,`,',"}
should have the character escaped with `\&'. Typical syntax is shown in
the first content macro displayed below, `.Ad', and the syntax for enclo-
sure/quoting macros is shown in Enclosure and Quoting Macros.
Address Macro
The address macro constructs an address of the form ad-
dr1[,addr2[,addr3]].
Usage: .Ad address ... { . , ; : ( ) [ ]}
.Ad addr1 addr1
.Ad addr1 . addr1.
.Ad addr1 , file2 addr1, file2
.Ad f1 , f2 , f3 : f1, f2, f3:
.Ad addr ) ) , addr)),
It is an error to call .Ad without arguments. .Ad is callable by other
macros and may call other macros.
Argument Macro
The .Ar argument macro may be used whenever a command line argument is
referenced.
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)),
If .Ar is called without arguments `file ...' is assumed. The .Ar macro
may call other macros, and may be called by other macros.
Angle Bracket Quote/Enclosure
Encloses a string or strings in between angle brackets. The macro `.Aq'
encloses the remaining arguments on the macro command line, and the `.Ao'
(angle open) and `.Ac' (angle close) macros may be used across one or
more lines.
Usage: .Aq string ... { . , ; : ( ) [ ]}
.Aq <>
.Aq string. <string.>
.Aq string . <string>.
.Aq stdio.h <stdio.h>
.Aq Ar ctype.h ) , <ctype.h>),
See Enclosure Macros for discussion and Options for examples of the open
and close macros `.Ac' and `.Ao'. `.Aq' is callable by other macros and
may call other macros.
Bracket Quotes/Enclosure
Bracket quotes should be used when the string being bracketed is not an
option string. The brackets for an option may be different than the de-
fault brackets. The macro `.Bq' encloses the remaining arguments on a
macro command line and the macros `.Bo' and `.Bc' may be used across one
or more lines.
Usage: .Bq string ... { . , ; : ( ) [ ]}
The .Bq macro exists for statements which use other macros: [Greek,
French]. This was done with:
.Bq Em Greek , French .
It also could have been done using the prefix macro:
.Pf [ Em Greek , French ] .
See Enclosure Macros for discussion and Options for examples of the open
and close macros `.Bc' and `.Bo'. The `.Bq' macro is callable and may
call other macros.
Configuration Declaration (section four only)
The `.Cd' macro is used to demonstrate a config(8) declaration for a de-
vice interface in a section four manual. This macro accepts quoted argu-
ments (double quotes only).
device le0 at scode? produced by: `.Cd device le0 at scode?'.
Command Modifier
The command modifier is identical to the `.Fl' (flag) command with the
exception the `.Cm' macro does not assert a dash in front of every argu-
ment. Traditionally flags are marked by the preceding dash, some commands
or subsets of commands do not use them. Command modifiers may also be
specified in conjunction with interactive commands such as editor com-
mands. See Flags.
Double Quote macro/Enclosure
The `.Dq' double quote encloses any remaining strings on the command line
with double quotes. Punctuation is placed after the end quote. The
macros `.Do' and `.Dc' may be used across one or more lines.
Usage: .Dq string ... { . , ; : ( ) [ ]}
.Dq ``''
.Dq string. ``string.''
.Dq string abc . ``string abc''.
.Dq '^[A-Z]' ``'^[A-Z]'''
.Dq Ar pattern ) ) , ``pattern'')),
If `.Dq' is called with no arguments ``'' is assumed. The `.Dq' macro may
call or be called by other macros. See Enclosure Macros for discussion
of `.Dc' and `.Do' macro types.
Defined Variables
A variable which is defined in an include file is specified by the macro
`.Dv'.
Usage: .Dv defined_variable ... { . , ; : ( ) [ ]}
.Dv MAXHOSTNAMELEN MAXHOSTNAMELEN
.Dv TIOCGPGRP ) TIOCGPGRP)
It is an error to call `.Dv' without arguments. `.Dv' may call other
macros and may be called by other macros.
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 emphasis can be forced across several lines of text by using the
`.Bf' macro discussed in Modes under PAGE LAYOUT.
The `.Em' macro is callable and may call other macros. It is an error to
call `.Em' without arguments.
Enclosure and Quoting Macros
The concept of enclosure is similar to quoting. The object is to enclose
a string or more between a pair of characters like quotes or parentheses.
The terms quoting and enclosure are used interchangeably throughout this
document. Many of the one line enclosure macros end end in small letter
`q' to give a hint of quoting, but there are a few exceptions (the macros
`.En', `.Fn' and `.Op' are also enclosure macros). For each enclosure
macro there is also a pair of open and close macros which end in small
letters `o' and `c' respectively. These can be used across one or more
lines of text and while they cannot be nested, the one line quote macros
can be used inside of them. For a good example of one these macros, see
Options.
quote close open function result
.Aq, .Ac, .Ao Angle Bracket Enclosure <string>
.Bq, .Bc, .Bo Bracket Enclosure [string]
.Dq, .Dc, .Do Double Quote ``string''
.Ec, .Eo Enclose String (in XX) XXstringXX
.Fn, .Fc, .Fo Function Enclosure function(string)
.Op, .Oc, .Oo Option Enclosure [string]
.Pq, .Pc, .Po Parenthesis Enclosure (string)
.Qq, .Qc, .Qo Straight Double Quote "string"
.Sq, .Sc, .So Single Quote `string'
.Xc, .Xo Extend Argument --
The macros `.Eo' and `.Ec' allow a user to specify an open and close with
the first argument as the opening or closing string respectively.
Errno's (Section two only)
The `.Er' errno macro specifies the error return value for section two
library routines. The second example below shows `.Er' used with the
`.Bq' macro, as it would be used in a section two manual page.
Usage: .Er ERRNOTYPE ... { . , ; : ( ) [ ]}
.Er ENOENT ENOENT
.Er ENOENT ) ; ENOENT);
.Bq Er ENOTDIR [ENOTDIR]
It is an error to call `.Er' without arguments. The `.Er' macro is
callable and may call other macros.
Environment Variables
The `.Ev' macro specifies a environment variable.
Usage: .Ev argument ... { . , ; : ( ) [ ]}
.Ev DISPLAY DISPLAY
.Ev PATH . PATH.
.Ev PRINTER ) ) , PRINTER)),
It is an error to call `.Ev' without arguments. The `.Ev' macro is
callable by other macros and may call other macros.
Function Argument
The `.Fa' macro is used to refer to function arguments (parameters) out-
side of the SYNOPSIS section of the manual or inside the SYNOPSIS section
should a parameter list be too long for the `.Fn' macro and the enclosure
macros `.Fo' and `.Fc' must be used. `.Fa' may also be used to refer to
structure members.
Usage: .Fa function_argument ... { . , ; : ( ) [ ]}
.Fa d_namlen ) ) , dnamlen)),
.Fa iov_len iovlen
It is an error to call `.Fa' without arguments. `.Fa' is callable by
other macros and may call other macros.
Function Declaration
The `.Fd' macro is used in the SYNOPSIS section with section two or three
functions. The `.Fd' macro does not call other macros and is not callable
by other macros.
Usage: .Fd include_file (or defined variable)
In the SYNOPSIS section a `.Fd' request 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 decla-
ration for the next function.
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 with out the
dash.
Usage: .Fl argument ... { . , ; : ( ) [ ]}
.Fl -
.Fl cfv -cfv
.Fl cfv . -cfv.
.Fl s v t -s -v -t
.Fl - , --,
.Fl xyz ) , -xyz),
The `.Fl' macro without any arguments results in a dash representing
stdin/stdout. Note that giving `.Fl' a single dash, will result in two
dashes. The `.Fl' macro is callable and may call other macros.
Functions (library routines)
The .Fn macro is modeled on ANSI C conventions.
Usage: .Fn [type] function [[type] params ... { . , ; : ( ) [ ]}]
.Fn getchar getchar()
.Fn strlen ) , strlen()),
.Fn "int align" "const * char *sptrs", int align(const * char *sptrs),
It is an error to call `.Fn' without any arguments. The `.Fn' macro is
callable by other macros and may call other macros, but note that any
call to another macro signals the end of the `.Fn' call (it will close-
paren at that point).
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. At the moment, `.Fn' does not check its word boundaries
against troff line lengths and may split across a newline ungracefully.
This will be fixed in the near future.
Function Type
This macro is intended for the SYNOPSIS section. It may be used anywhere
else in the manpage 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 page break allowing the function name to appear on
the next line).
Usage: .Ft type ... { . , ; : ( ) [ ]}
.Ft struct stat struct stat
The `.Ft' request is not callable by other macros.
Interactive Commands
The `.Ic' macro designates an interactive or internal command.
Usage: .Li argument ... { . , ; : ( ) [ ]}
.Ic :wq :wq
.Ic do while {...} do while {...}
.Ic setenv , unsetenv setenv, unsetenv
It is an error to call `.Ic' without arguments. The `.Ic' macro may call
other macros and is callable.
Literals
The `.Li' literal macro may be used for special characters, variable con-
stants, 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 `.Li' macro is callable by other macros and may call other macros.
Name Macro
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 the `.Ic' is nearly identical to `.Nm', it can not recall
the first argument it was invoked with.
Usage: .Nm argument ... { . , ; : ( ) [ ]}
.Nm mdoc.sample mdoc.sample
.Nm -mdoc -mdoc.
.Nm foo ) ) , foo)),
.Nm mdoc.sample
The `.Nm' macro is callable by other macros and may call other macros.
No-Op or Normal Text Macro
The macro .No is a hack for words in a macro command line which should
not be formatted and follows the conventional syntax for content macros.
No Space Macro
The `.Ns' macro eliminates unwanted spaces in between macro requests. It
is useful for old style argument lists where there is no space between
the flag and argument:
.Op Fl I Ns Ar directory produces [-Idirectory]
Note: the `.Ns' macro always invokes the `.No' macro after eliminating
the space unless another macro name follows it. The macro `.Ns' is
callable and may call other macros.
Options
The `.Op' macro places option brackets around the any remaining arguments
on the command line, and places any trailing punctuation outside the
brackets. The macros `.Oc' and `.Oo' may be used across one or more
lines.
Usage: .Op options ... { . , ; : ( ) [ ]}
.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]
The `.Oc' and `.Oo' macros:
.Oo
.Op Fl k Ar kilobytes
.Op Fl i Ar interval
.Op Fl c Ar count
.Oc
Produce: [[-k kilobytes] [-i interval] [-c count]]
The macros `.Op', `.Oc' and `.Oo' are callable and may call other macros.
Parenthesis Quote/Enclosure
Macros .Pq, .Pc and .Po follow the conventions for a typical quoting
macros, see Enclosure Macros and Options above.
Pathnames
The `.Pa' macro formats path or file names.
Usage: .Pa pathname { . , ; : ( ) [ ]}
.Pa /usr/share /usr/share
.Pa /tmp/fooXXXXX ) . /tmp/fooXXXXX).
The `.Pa' macro is callable by other macros and may call other macros.
Single Quotes/Enclosure
See Enclosure Macros. See Double Quote/Enclosure above. The single quot-
ing macro `.Sq' works in the identical manner as `.Dq.'
Prefix Macro
The `.Pf' macro is a short cut for combining two strings together, the
first of which is in the default font, and the second a content specified
string.
.Pf ( Fa name2 becomes (name2
The `.Pf' macro is not callable, but may call other macros. The `.Ns'
macro performs the analogous suffix function.
Section Cross References
The `.Sx' macro designates a reference to a section header within the
same document. It is callable by other macros and may call other macros.
.Sx FILES FILES
References and Citations
The following macros make a modest attempt to handle references. At
best, the macros make it convenient to manually drop in a subset of refer
style references.
.Rs Reference Start. Causes a line break and begins collection
of reference information until the reference end macro is
read.
.Re Reference End. The reference is printed.
.%A Reference author name, one name per invocation.
.%B Book title.
.%J Journal title.
.%N Issue number.
.%O Optional information.
.%R Report name.
.%T Title of article.
.%V Volume(s).
The macros beginning with `%' are not callable, but may call only the
trade name macro which returns to its caller. The purpose is to allow
trade names to be pretty printed in troff output. WARNING: this has very
few trade names defined at the moment and will print unknown trade names
in the default font.
Symbolic
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 `.Sy' macro is callable by other macros and may call other macros,
except in the second form. Arguments to `.Sy' may be quoted.
Variables
Generic variable reference:
Usage: .Va variable ... { . , ; : ( ) [ ]}
.Va count count
.Va settimer, settimer,
.Va int *prt ) : int *prt):
.Va char s ] ) ) , char s])),
It is an error to call `.Va' without any arguments. The `.Va' macro is
callable by other macros and may call other macros.
Cross References
The `.Xr' macro expects the first argument to be a manual page name, and
the second argument, if it exists, to be either a section page number or
punctuation. Any remaining arguments are assumed to be punctuation.
Usage: .Xr manpage [1,...,8] { . , ; : ( ) [ ]}
.Xr mdoc mdoc
.Xr mdoc , mdoc,
.Xr mdoc 7 mdoc(7)
.Xr mdoc 7 ) ) , mdoc(7))),
The `.Xr' macro is callable by other macros and may call other macros.
It is an error to call `.Xr' without any arguments.
Extended Arguments
The .Xo and .Xc macros allow one to extend an argument list on a macro
boundary. Argument lists cannot be extended within a macro which expects
all of its arguments on one line such as `.Op'.
PAGE LAYOUT MACROS
Section Headers
The first three `.Sh' section header macros list below are required in
every man page. The remaining section headers are recommended at the dis-
cretion of the author writing the manual page. The `.Sh' macro can take
up to nine arguments. It may call other macros, but it may not be called
by other macros.
.Sh NAME The `.Sh NAME' macro is mandatory. If not specified, the
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 separates the
subject name from the third item, which is the description.
The description should be the most terse and lucid possi-
ble, as the space available is small.
.Sh SYNOPSIS The SYNOPSIS section describes the typical usage of the
subject of a man page. The macros required are either
`.Nm', `.Cd', or `.Fn' (and possibly `.Fd', `.Ft' macros).
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, 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 paragraph on the command, function or file, fol-
lowed by a lexical list of options and respective explana-
tions. To create such a list, the `.Bl' begin-list, `.It'
list-item and `.El' end-list macros are used (see Lists and
Columns below).
The following `.Sh' section headers are part of the preferred 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 behaviour and/or usage.
.Sh EXAMPLES
There are several ways to create examples. See the EXAMPLES
section below for details.
.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 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. At this time refer(1) style references are not
accommodated.
.Sh STANDARDS
If the command, library function or file adheres to a specific
implementation such as POSIX 1003.1 or ANSI C X3.159-1989 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 outlined historically in this section.
.Sh AUTHORS
Credits, if need be, should be placed here.
.Sh DIAGNOSTICS
Diagnostics from a command should be placed in this section.
.Sh ERRORS
Specific error handling, especially from library functions (man
page sections 2 and 3) should go here. The `.Er' macro is used
to specify an errno.
.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 LAYOUT MACROS
Paragraphs and Line Spacing.
.Pp The .Pp paragraph command may be used to specify a line space
where necessary. The macro is not necessary after a `.Sh' or
`.Ss' macro or before a `.Bl' macro. (The `.Bl' macro asserts a
vertical distance unless the -compact flag is given).
Examples and Displays
There are five types of displays, a quickie one line indented display
`.D1', a quickie one line literal display `.Dl', a block literal, block
filled and block ragged which use the `.Bd' begin-display and `.Ed' end-
display macros.
.D1 (D-one) Display one line of indented text. Arguments are checked to
see if they are callable.
.D1 Fl ldghfstru
produces:
-ldghfstru
.Dl (D-ell) Display one line of indented literal text. The `.Dl' exam-
ple macro has been used throughout this file. It allows the indent
(display) of one line of text. Its default font is set to constant
width (literal) however `.Dl' does check arguments to see it they
are callable. Macros called from .Dl should be content macros;
calling macros from the page layout section is redundant and may
cause unpredictable errors.
.Dl % ls -ldg /usr/local/bin
produces:
% ls -ldg /usr/local/bin
.Bd Begin-display. The `.Bd' display must be ended with the `.Ed' macro.
Displays may be nested within displays and lists. `.Bd' has the
following syntax:
.Bd display-type [offset offset_value]
The display-type must be one of the following four types and may
have an offset specifier for indentation: `.Bd'.
-ragged Display a block of text as typed, right (and left) margin
edges are left ragged.
-filled Display a filled (formatted) block. The block of text is
formatted (the edges are filled - not left ragged).
-literal Display a literal block, useful for source code or simple
tabbed or spaced text.
-file filename
The file name following the -file flag is read and dis-
played. Literal mode is asserted and tabs are set at 8
constant width character intervals, however any
troff/-mdoc commands in 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 unfor-
tunately, the block merely gets left aligned
about an imaginary center margin.
indent Indents by one default indent value or tab. The
default indent value is also used for the `.D1'
display so one can be guaranteed of the two types
of displays lining up. This indent is normally
set to 6n or about two thirds of an inch (six
constant width characters).
indent-two
Indents two times the default indent value.
right This left aligns the block about two inches from
the right side of the page. This macro also needs
work and perhaps may never be right in troff.
.Ed End-display.
Tagged 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. Columns may be used inside
of lists, but lists are unproven inside of columns.
In addition, several list attributes may be specified such as the width
of a tag, the list offset, and compactness specified (blank lines between
items allowed or disallowed). The following list types are accepted by
`.Bl':
-bullet
-item
-enum
These three are the simplest types of lists. Once the `.Bl' macro has
been given, items in the list are merely indicated by a line consisting
solely of the `.It' macro. For example, the source text for a simple enu-
merated list would look like:
.Bl -enum -compact
.It
Item one goes here.
.It
And item two here.
.It
Lastly item three goes here.
.El
The results:
1. Item one goes here.
2. And item two here.
3. Lastly item three goes here.
A simple bullet list construction:
.Bl -bullet -compact
.It
Bullet one goes here.
.It
Bullet two here.
.El
Produces:
o Bullet one goes here.
o Bullet two here.
-tag
-diag
-hang
-ohang
-inset
These list-types collect arguments specified with the `.It' macro and
create a label which may be inset into the forth coming text, hanged (ex-
dented) from the forth coming text, overhanged set above the forth coming
paragraph or tagged (exdented and offset). This list was constructed with
the `-ohang' list-type. The `.It' macro may call any callable macros for
the inset, hang and tag list-types, but will not call macros for the diag
type. 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.
Diag Diag lists create section four diagnostic lists and are simi-
lar to inset lists except callable macros are ignored.
Hang Hanged labels are a matter of taste.
Ohang Over hanging labels are nice when space is constrained.
Inset Inset labels are useful for controlling blocks of paragraphs
and are valuable for converting -mdoc manuals to other formats.
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
Over hanging 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
Here is a hanged list with just one item:
Hanged labels appear similar to tagged lists when the label is
smaller than the label width.
Longer hanged list labels blend in to 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 in to the paragraph unlike
tagged paragraph labels.
.El
The tagged list which follows uses an optional width specifier to control
the width of the tag.
SL 10 sleep time of the process (seconds blocked)
PAGEIN 10 number of disk i/o's resulting from references by the
process to pages not loaded in core.
UID 10 numerical user-id of process owner
PPID 10 numerical id of parent of process process priority (non-
positive when in non-interruptible wait)
The raw text:
.Bl -tag -width "PAGEIN 10" -compact -offset indent
.It SL 10
sleep time of the process (seconds blocked)
.It PAGEIN 10
number of disk i/o's resulting from references
by the process to pages not loaded in core.
.It UID 10
numerical user-id of process owner
.It PPID 10
numerical id of parent of process process priority
(non-positive when in non-interruptible wait)
.El
Acceptable width specifiers:
-width Fl sets the width to the default width for a flag. All
callable macros have a default width value. The
`.Fl', value is presently set to ten constant width
characters or about five sixth of an inch.
-width 24n sets the width to 24 constant width characters or
about two inches. The `n' is absolutely necessary
for the scaling to work correctly.
-width ENAMETOOLONG
sets width to the constant width length of the string
given.
-width "int mkfifo"
again, the width is set to the constant width of the
string given.
If a width is not specified for the tag list type, the first time `.It'
is invoked, an attempt is made to determine an appropriate width. If the
first argument to `.It' is a callable macro, the default width for that
macro will be used as if the macro name had been supplied as the width.
However, if another item in the list is given with a different callable
macro name, a new and nested list is assumed. Here is an involved example
of a self nesting list:
DIAGNOSTICS
The debugging facilities for -mdoc are limited, but can help detect sub-
tle errors such as the collision of an argument name with an internal
register or macro name. (A what?) A register is an arithmetic storage
class for troff with a one or two character name. All registers internal
to -mdoc for troff are two characters and of the form <upper-
case><lowercase> such as `Ar', <lowercase><uppercase> as `aR' or <upper
or lower letter><digit> as `C1'. And adding to the muddle, troff has its
own internal registers all of which are either two lower case characters
or a dot plus a letter or meta-character character. In one of the intro-
duction examples, it was shown how to prevent the interpretation of a
macro name with the escape sequence `\&'. This is sufficient for the in-
ternal register names also.
If a non-escaped register name is given in the argument list of a request
unpredictable behaviour will occur. In general, anytime huge portions of
text do not appear where expected in the output, or small strings such as
list tags disappear, chances are there is a misunderstanding about an ar-
gument type in the argument list. Your mother never intended for you to
remember this evil stuff - so here is a way to find out whether or not
your arguments are valid: The `.Db' (debug) macro displays the interpre-
tation of the argument list for most macros. Macros such as the `.Pp'
(paragraph) macro do not contain debugging information. All of the
callable macros do, and it is strongly advised whenever in doubt, turn on
the `.Db' macro.
Usage: .Db [on | off]
An example of a portion of text with the debug macro placed above and be-
low an artificially created problem (a flag argument `aC' which should be
`\&aC' in order to work):
.Db on
.Op Fl aC Ar file )
.Db off
The resulting output:
DEBUGGING ON
DEBUG(argv) MACRO: `.Op' Line #: 2
Argc: 1 Argv: `Fl' Length: 2
Space: `' Class: Executable
Argc: 2 Argv: `aC' Length: 2
Space: `' Class: Executable
Argc: 3 Argv: `Ar' Length: 2
Space: `' Class: Executable
Argc: 4 Argv: `file' Length: 4
Space: ` ' Class: String
Argc: 5 Argv: `)' Length: 1
Space: ` ' Class: Closing Punctuation or suffix
MACRO REQUEST: .Op Fl aC Ar file )
DEBUGGING OFF
The first line of information tells the name of the calling macro, here
`.Op', and the line number it appears on. If one or more files are in-
volved (especially if text from another file is included) the line number
may be bogus. If there is only one file, it should be accurate. The
second line gives the argument count, the argument (`Fl') and its length.
If the length of an argument is two characters, the argument is tested to
see if it is executable (unfortunately, any register which contains a
non-zero value appears executable). The third line gives the space al-
lotted for a class, and the class type. The problem here is the argument
aC should not be executable. The four types of classes are string, exe-
cutable, closing punctuation and opening punctuation. The last line
shows the entire argument list as it was read. In this next example, the
offending `aC' is escaped:
.Db on
.Em An escaped \&aC
.Db off
DEBUGGING ON
DEBUG(fargv) MACRO: `.Em' Line #: 2
Argc: 1 Argv: `An' Length: 2
Space: ` ' Class: String
Argc: 2 Argv: `escaped' Length: 7
Space: ` ' Class: String
Argc: 3 Argv: `aC' Length: 2
Space: ` ' Class: String
MACRO REQUEST: .Em An escaped &aC
DEBUGGING OFF
The argument `\&aC' shows up with the same length of 2 as the `\&' se-
quence produces a zero width, but a register named `\&aC' was not found
and the type classified as string.
Other diagnostics consist of usage statements and are self explanatory.
FILES
/usr/share/tmac/tmac.doc manual macro package
/usr/share/misc/mdoc.template template for writing a man page
HISTORY
4.4 BSD
SEE ALSO
mdoc(7), man(1), troff(1)
BUGS
Undesirable hyphenation on the dash of a flag argument is not yet re-
solved, and causes occasional mishaps in the DESCRIPTION section. (line
break on the hyphen).
Predefined strings are not declared in documentation.
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. Right now it separates the last parenthesis, and sometimes
looks ridiculous if a line is in fill mode.
The method used to prevent header and footer page breaks (other than the
initial header and footer) when using nroff seems to be putting out a
partially filled line at the bottom of the page leaving an unsightly
blank space.
The list and display macros to not do any keeps and certainly should be
able to.
BSDI BSD/386 March 27, 1993 18