path: root/man.7

.\"	$Id: man.7,v 1.18 2009/07/04 09:00:41 kristaps Exp $
.\"
.\" Copyright (c) 2009 Kristaps Dzonsons <kristaps@kth.se>
.\"
.\" Permission to use, copy, modify, and distribute this software for any
.\" purpose with or without fee is hereby granted, provided that the above
.\" copyright notice and this permission notice appear in all copies.
.\"
.\" THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
.\" WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
.\" MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
.\" ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
.\" WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
.\" ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
.\" OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
.\"
.Dd $Mdocdate: July 4 2009 $
.Dt MAN 7
.Os
.\" SECTION
.Sh NAME
.Nm man
.Nd man language reference
.\" SECTION
.Sh DESCRIPTION
The
.Nm man
language was historically used to format 
.Ux
manuals.  This reference document describes the syntax and structure of
this language.
.Pp
.Em \&Do not
use 
.Nm
to write your manuals.  Use the
.Xr mdoc 7
language, instead.
.\" PARAGRAPH
.Pp
An
.Nm
document follows simple rules:  lines beginning with the control
character 
.Sq \&.
are parsed for macros.  Other lines are interpreted within the scope of
prior macros:
.Bd -literal -offset indent
\&.SH Macro lines change control state.
Other lines are interpreted within the current state.
.Ed
.\" SECTION
.Sh INPUT ENCODING
.Nm
documents may contain only graphable 7-bit ASCII characters, the
space character
.Sq \  ,
and tabs
.Sq \et . 
All manuals must have
.Ux
.Sq \en
line termination.  
.Pp
Blank lines are acceptable; where found, the output will assert a
vertical space.
.Pp
The
.Sq \ec
escape is common in historical
.Nm
documents; if encountered at the end of a word, it ensures that the
subsequent word isn't off-set by whitespace.
.\" SUB-SECTION
.Ss Comments
Anything following a
.Sq \e" 
delimiter is considered a comment (unless the 
.Sq \e
itself has been escaped) and is ignored to the end of line.
Furthermore, a macro line with only a control character
.Sq \. ,
optionally followed by whitespace, is ignored.
.\" SUB-SECTION
.Ss Special Characters
Special character sequences begin with the escape character
.Sq \e
followed by either an open-parenthesis 
.Sq \&(
for two-character sequences; an open-bracket
.Sq \&[
for n-character sequences (terminated at a close-bracket
.Sq \&] ) ;
or a single one-character sequence.
.Pp
Characters may alternatively be escaped by a slash-asterisk,
.Sq \e* ,
with the same combinations as described above.
.Pp
Terms may also be text-decorated using the
.Sq \ef
escape followed by a text-decoration letter: B (bold), I, (italic), or P
and R (Roman, or reset).
.\" SUB-SECTION
.Ss Whitespace
Unless specifically escaped, consecutive blocks of whitespace are pruned
from input.  These are later re-added, if applicable, by a front-end
utility such as
.Xr mandoc 1 .
.\" SECTION
.Sh STRUCTURE
Each
.Nm
document must contain contains at least the
.Sq \&.TH
macro describing the document's section and title.  It may occur
anywhere in the document, although conventionally, it appears as the
first macro.
.Pp
Beyond the 
.Sq \&.TH ,
at least one macro or text node must appear in the document.
.\" SECTION
.Sh SYNTAX
Macros are one to three three characters in length and begin with a
control character ,
.Sq \&. ,
at the beginning of the line.  An arbitrary amount of whitespace may
sit between the control character and the macro name.  Thus,
.Sq \&.PP
and
.Sq \&.\ \ \ \&PP
are equivalent.
.Pp
All 
.Nm
macros follow the same structural rules:
.Bd -literal -offset indent
\&.YO \(lBbody...\(rB 
.Ed
.Pp
The
.Dq body
consists of zero or more arguments to the macro.
.Pp
.Nm
has a primitive notion of multi-line scope for the following macros: 
.Sq \&.TM ,
.Sq \&.SM ,
.Sq \&.SB ,
.Sq \&.BI ,
.Sq \&.IB ,
.Sq \&.BR ,
.Sq \&.RB ,
.Sq \&.R ,
.Sq \&.B ,
.Sq \&.I ,
.Sq \&.IR 
and
.Sq \&.RI .
When these macros are invoked without arguments, the subsequent line is
considered a continuation of the macro.  Thus:
.Bd -literal -offset indent 
\&.RI 
foo
.Ed
.Pp
is equivalent to 
.Sq \&.RI foo .
If two consecutive lines exhibit the latter behaviour,
an error is raised.  Thus, the following is not acceptable:
.Bd -literal -offset indent 
\&.RI 
\&.I 
Hello, world.
.Ed
.Pp
The
.Sq \&.TP
macro is similar, but does not need an empty argument line to trigger
the behaviour.
.\" SECTION
.Sh MACROS
This section contains a complete list of all 
.Nm
macros and corresponding number of arguments.
.Pp
.Bl -column "MacroX" "Arguments" -compact -offset indent
.It Em Macro Ta Em Arguments
.It \&.TH    Ta    >1, <6
.It \&.SH    Ta    >0
.It \&.SS    Ta    >0
.It \&.TP    Ta    n
.It \&.LP    Ta    0
.It \&.PP    Ta    0
.It \&.P     Ta    0
.It \&.IP    Ta    <3
.It \&.HP    Ta    <2
.It \&.SM    Ta    n
.It \&.SB    Ta    n
.It \&.BI    Ta    n
.It \&.IB    Ta    n
.It \&.BR    Ta    n
.It \&.RB    Ta    n
.It \&.R     Ta    n
.It \&.B     Ta    n
.It \&.I     Ta    n
.It \&.IR    Ta    n
.It \&.RI    Ta    n
.El
.Pp
Although not historically part of the
.Nm
system, the following macros are also supported:
.Pp
.Bl -column "MacroX" "Arguments" -compact -offset indent
.It Em Macro Ta Em Arguments
.It \&.br    Ta    0
.It \&.i     Ta    n
.El
.Pp
These follow the same calling conventions as the above
.Nm
macros.
.\" SECTION
.Sh COMPATIBILITY
See
.Xr mdoc 7
for groff compatibility notes.
.\" SECTION
.Sh SEE ALSO
.Xr mandoc 1 ,
.Xr mandoc_char 7
.\" SECTION
.Sh AUTHORS
The
.Nm
utility was written by 
.An Kristaps Dzonsons Aq kristaps@kth.se .
.\" SECTION
.Sh CAVEATS
Do not use this language.  Use
.Xr mdoc 7 ,
instead.