better error message if mandocd is not found

[mandoc.git] / roff.7

diff --git a/roff.7 b/roff.7
index ad6784537d666adb87f0d82b9730e1dbbc6fa049..6c2e3583f69b9e899e53e8efad50697f3284c879 100644 (file)
--- a/roff.7
+++ b/roff.7
@@ -1,7 +1,7 @@
-.\"    $Id: roff.7,v 1.107 2018/10/04 15:32:09 schwarze Exp $
+.\"    $Id: roff.7,v 1.116 2021/09/18 12:23:06 schwarze Exp $

 .\"
 .\" Copyright (c) 2010, 2011, 2012 Kristaps Dzonsons <kristaps@bsd.lv>
 .\"
 .\" Copyright (c) 2010, 2011, 2012 Kristaps Dzonsons <kristaps@bsd.lv>

-.\" Copyright (c) 2010-2018 Ingo Schwarze <schwarze@openbsd.org>
+.\" Copyright (c) 2010-2019 Ingo Schwarze <schwarze@openbsd.org>

 .\"
 .\" Permission to use, copy, modify, and distribute this software for any
 .\" purpose with or without fee is hereby granted, provided that the above
 .\"
 .\" Permission to use, copy, modify, and distribute this software for any
 .\" purpose with or without fee is hereby granted, provided that the above


@@ -15,7 +15,7 @@
 .\" ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
 .\" OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 .\"
 .\" ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
 .\" OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 .\"

-.Dd $Mdocdate: October 4 2018 $
+.Dd $Mdocdate: September 18 2021 $

 .Dt ROFF 7
 .Os
 .Sh NAME
 .Dt ROFF 7
 .Os
 .Sh NAME


@@ -44,7 +44,8 @@ utility supports a subset of
 requests and escapes.
 Even though this manual page lists all
 .Nm
 requests and escapes.
 Even though this manual page lists all
 .Nm

-requests, it only has partial information about requests not supported by
+requests and escape sequences, it only contains partial information
+about requests not supported by

 .Xr mandoc 1
 and about language features that do not matter for manual pages.
 For complete
 .Xr mandoc 1
 and about language features that do not matter for manual pages.
 For complete


@@ -86,7 +87,7 @@ indicates the start of an escape sequence, used for example for
 .Sx Comments
 and
 .Sx Special Characters .
 .Sx Comments
 and
 .Sx Special Characters .

-For a listing of escape sequences, consult the
+For a complete listing of escape sequences, consult the

 .Sx ESCAPE SEQUENCE REFERENCE
 below.
 .Ss Comments
 .Sx ESCAPE SEQUENCE REFERENCE
 below.
 .Ss Comments


@@ -132,20 +133,73 @@ One-letter backslash escape.
 See
 .Xr mandoc_char 7
 for a complete list.
 See
 .Xr mandoc_char 7
 for a complete list.

-.Ss Text Decoration
-Terms may be text-decorated using the
-.Sq \ef
-escape followed by an indicator: B (bold), I (italic), R (regular), or P
-(revert to previous mode).
-A numerical representation 3, 2, or 1 (bold, italic, and regular,
-respectively) may be used instead.
-The indicator or numerical representative may be preceded by C
-(constant-width), which is ignored.
-.Pp
-The two-character indicator
-.Sq BI
-requests a font that is both bold and italic.
-It may not be portable to old roff implementations.
+.Ss Font Selection
+In
+.Xr mdoc 7
+and
+.Xr man 7
+documents, fonts are usually selected with macros.
+The
+.Ic \ef
+escape sequence and the
+.Ic \&ft
+request can be used to manually change the font,
+but this is not recommended in
+.Xr mdoc 7
+documents.
+Such manual font changes are overridden by many subsequent macros.
+.Pp
+The following fonts are supported:
+.Pp
+.Bl -tag -width CW -offset indent -compact
+.It Cm B
+Bold font.
+.It Cm BI
+A font that is both bold and italic.
+.It Cm CB
+Bold constant width font.
+Same as
+.Cm B
+in terminal output.
+.It Cm CI
+Italic constant width font.
+Same as
+.Cm I
+in terminal output.
+.It Cm CR
+Regular constant width font.
+Same as
+.Cm R
+in terminal output.
+.It Cm CW
+An alias for
+.Cm CR .
+.It Cm I
+Italic font.
+.It Cm P
+Return to the previous font.
+If a macro caused a font change since the last
+.Ic \ef
+eascape sequence or
+.Ic \&ft
+request, this returns to the font before the last font change in
+the macro rather than to the font before the last manual font change.
+.It Cm R
+Roman font.
+This is the default font.
+.It Cm 1
+An alias for
+.Cm R .
+.It Cm 2
+An alias for
+.Cm I .
+.It Cm 3
+An alias for
+.Cm B .
+.It Cm 4
+An alias for
+.Cm BI .
+.El

 .Pp
 Examples:
 .Bl -tag -width Ds -offset indent -compact
 .Pp
 Examples:
 .Bl -tag -width Ds -offset indent -compact


@@ -156,12 +210,6 @@ Write in \fIitalic\fP, then return to previous font mode.
 .It Li \ef(BIbold italic\efP
 Write in \f(BIbold italic\fP, then return to previous font mode.
 .El
 .It Li \ef(BIbold italic\efP
 Write in \f(BIbold italic\fP, then return to previous font mode.
 .El

-.Pp
-Text decoration is
-.Em not
-recommended for
-.Xr mdoc 7 ,
-which encourages semantic annotation.

 .Ss Whitespace
 Whitespace consists of the space character.
 In text lines, whitespace is preserved within a line.
 .Ss Whitespace
 Whitespace consists of the space character.
 In text lines, whitespace is preserved within a line.


@@ -199,9 +247,9 @@ centimetre
 .It i
 inch
 .It P
 .It i
 inch
 .It P

-pica (~1/6 inch)
+pica (1/6 inch)

 .It p
 .It p

-point (~1/72 inch)
+point (1/72 inch)

 .It f
 scale
 .Sq u
 .It f
 scale
 .Sq u


@@ -221,7 +269,7 @@ character
 .It u
 default horizontal span for the terminal
 .It M
 .It u
 default horizontal span for the terminal
 .It M

-mini-em (~1/100 em)
+mini-em (1/100 em)

 .El
 .Pp
 Using anything other than
 .El
 .Pp
 Using anything other than


@@ -267,12 +315,18 @@ delimiters
 The proper spacing is also intelligently preserved if a sentence ends at
 the boundary of a macro line.
 .Pp
 The proper spacing is also intelligently preserved if a sentence ends at
 the boundary of a macro line.
 .Pp

+If an input line happens to end with a period, exclamation or question
+mark that isn't the end of a sentence, append a zero-width space
+.Pq Sq \e& .
+.Pp

 Examples:
 .Bd -literal -offset indent -compact
 Do not end sentences mid-line like this.  Instead,
 end a sentence like this.
 A macro would end like this:
 \&.Xr mandoc 1 \&.
 Examples:
 .Bd -literal -offset indent -compact
 Do not end sentences mid-line like this.  Instead,
 end a sentence like this.
 A macro would end like this:
 \&.Xr mandoc 1 \&.

+An abbreviation at the end of an input line needs escaping, e.g.\e&
+like this.

 .Ed
 .Sh REQUEST SYNTAX
 A request or macro line consists of:
 .Ed
 .Sh REQUEST SYNTAX
 A request or macro line consists of:


@@ -455,10 +509,9 @@ This is a Heirloom extension and currently unsupported.
 .It Ic \&br
 Break the output line.
 .It Ic \&break
 .It Ic \&br
 Break the output line.
 .It Ic \&break

-Break out of a
+Break out of the innermost

 .Ic \&while
 loop.
 .Ic \&while
 loop.

-Currently unsupported.

 .It Ic \&breakchar Ar char ...
 Optional line break characters.
 This is a Heirloom extension and currently ignored.
 .It Ic \&breakchar Ar char ...
 Optional line break characters.
 This is a Heirloom extension and currently ignored.


@@ -571,7 +624,7 @@ Its syntax can be either
 .Pp
 or
 .Bd -literal -offset indent
 .Pp
 or
 .Bd -literal -offset indent

-.Pf . Ic \&de Ar macroname Ar endmacro
+.Pf . Ic \&de Ar macroname endmacro

 .Ar definition
 .Pf . Ar endmacro
 .Ed
 .Ar definition
 .Pf . Ar endmacro
 .Ed


@@ -593,7 +646,7 @@ macros, whichever applies to the document in question.
 .Pp
 Specifying a custom
 .Ar endmacro
 .Pp
 Specifying a custom
 .Ar endmacro

-macro works in the same way as for
+works in the same way as for

 .Ic \&ig ;
 namely, the call to
 .Sq Pf . Ar endmacro
 .Ic \&ig ;
 namely, the call to
 .Sq Pf . Ar endmacro


@@ -860,11 +913,23 @@ This is a Heirloom extension and currently ignored.
 Enable or disable an OpenType feature.
 This is a Heirloom extension and currently ignored.
 .It Ic \&fi
 Enable or disable an OpenType feature.
 This is a Heirloom extension and currently ignored.
 .It Ic \&fi

-Switch to fill mode.
-See
-.Xr man 7 .
-Ignored in
-.Xr mdoc 7 .
+Break the output line and switch to fill mode,
+which is active by default but can be ended with the
+.Ic \&nf
+request.
+In fill mode, input from subsequent input lines is added to
+the same output line until the next word no longer fits,
+at which point the output line is broken.
+This request is implied by the
+.Xr mdoc 7
+.Ic \&Sh
+macro and by the
+.Xr man 7
+.Ic \&SH ,
+.Ic \&SS ,
+and
+.Ic \&EE
+macros.

 .It Ic \&fkern Ar font minkern
 Control the use of kerning tables for a font.
 This is a Heirloom extension and currently ignored.
 .It Ic \&fkern Ar font minkern
 Control the use of kerning tables for a font.
 This is a Heirloom extension and currently ignored.


@@ -890,27 +955,12 @@ This is a Heirloom extension and currently ignored.
 Conditionally define a special font.
 This is a groff extension and currently ignored.
 .It Ic \&ft Op Ar font
 Conditionally define a special font.
 This is a groff extension and currently ignored.
 .It Ic \&ft Op Ar font

-Change the font.
-The following
+Change the font; see
+.Sx Font Selection .
+The

 .Ar font
 .Ar font

-arguments are supported:
-.Bl -tag -width 4n -offset indent
-.It Cm B , BI , CB , 3 , 4
-switches to
-.Sy bold
-font
-.It Cm I , CI , 2
-switches to
-.Em underlined
-font
-.It Cm R , CR , CW , 1
-switches to normal font
-.It Cm P No "or no argument"
-switches back to the previous font
-.El
-.Pp
-This request takes effect only locally and may be overridden
-by macros and escape sequences.
+argument defaults to
+.Cm P .

 .It Ic \&ftr Ar newname Op Ar oldname
 Translate font name.
 This is a groff extension and currently ignored.
 .It Ic \&ftr Ar newname Op Ar oldname
 Translate font name.
 This is a groff extension and currently ignored.


@@ -1314,11 +1364,22 @@ Declare the need for the specified minimum vertical space
 before the next trap or the bottom of the page.
 Currently ignored.
 .It Ic \&nf
 before the next trap or the bottom of the page.
 Currently ignored.
 .It Ic \&nf

-Switch to no-fill mode.
-See
-.Xr man 7 .
-Ignored by
-.Xr mdoc 7 .
+Break the output line and switch to no-fill mode.
+Subsequent input lines are kept together on the same output line
+even when exceeding the right margin,
+and line breaks in subsequent input cause output line breaks.
+This request is implied by the
+.Xr mdoc 7
+.Ic \&Bd Fl unfilled
+and
+.Ic \&Bd Fl literal
+macros and by the
+.Xr man 7
+.Ic \&EX
+macro.
+The
+.Ic \&fi
+request switches back to the default fill mode.

 .It Ic \&nh
 Turn off automatic hyphenation mode.
 Currently ignored.
 .It Ic \&nh
 Turn off automatic hyphenation mode.
 Currently ignored.


@@ -1817,10 +1878,6 @@ The
 .Xr mandoc 1
 .Nm
 parser recognises the following escape sequences.
 .Xr mandoc 1
 .Nm
 parser recognises the following escape sequences.

-Note that the
-.Nm
-language defines more escape sequences not implemented in
-.Xr mandoc 1 .

 In
 .Xr mdoc 7
 and
 In
 .Xr mdoc 7
 and


@@ -1830,9 +1887,7 @@ described in the
 .Sx LANGUAGE SYNTAX
 section above.
 .Pp
 .Sx LANGUAGE SYNTAX
 section above.
 .Pp

-In
-.Xr mandoc 1 ,
-a backslash followed by any character not listed here
+A backslash followed by any character not listed here

 simply prints that character itself.
 .Bl -tag -width Ds
 .It Ic \e<newline>
 simply prints that character itself.
 .Bl -tag -width Ds
 .It Ic \e<newline>


@@ -1843,7 +1898,14 @@ on both lines together as if it were on a single input line.
 The escape sequence backslash-space
 .Pq Sq \e\ \&
 is an unpaddable space-sized non-breaking space character; see
 The escape sequence backslash-space
 .Pq Sq \e\ \&
 is an unpaddable space-sized non-breaking space character; see

-.Sx Whitespace .
+.Sx Whitespace
+and
+.Xr mandoc_char 7 .
+.It Ic \e!
+Embed text up to and including the end of the input line into the
+current diversion or into intermediate output without interpreting
+requests, macros, and escapes.
+Currently unsupported.

 .It Ic \e\(dq
 The rest of the input line is treated as
 .Sx Comments .
 .It Ic \e\(dq
 The rest of the input line is treated as
 .Sx Comments .


@@ -1860,8 +1922,16 @@ Macro argument expansion, see
 Hyphenation allowed at this point of the word; ignored by
 .Xr mandoc 1 .
 .It Ic \e&
 Hyphenation allowed at this point of the word; ignored by
 .Xr mandoc 1 .
 .It Ic \e&

-Non-printing zero-width character; see
-.Sx Whitespace .
+Non-printing zero-width character,
+often used for various kinds of escaping; see
+.Sx Whitespace ,
+.Xr mandoc_char 7 ,
+and the
+.Dq MACRO SYNTAX
+and
+.Dq Delimiters
+sections in
+.Xr mdoc 7 .

 .It Ic \e\(aq
 Acute accent special character; use
 .Ic \e(aa
 .It Ic \e\(aq
 Acute accent special character; use
 .Ic \e(aa


@@ -1870,6 +1940,10 @@ instead.
 .Sx Special Characters
 with two-letter names, see
 .Xr mandoc_char 7 .
 .Sx Special Characters
 with two-letter names, see
 .Xr mandoc_char 7 .

+.It Ic \e)
+Zero-width space transparent to end-of-sentence detection;
+ignored by
+.Xr mandoc 1 .

 .It Ic \e*[ Ns Ar name Ns Ic \&]
 Interpolate the string with the
 .Ar name .
 .It Ic \e*[ Ns Ar name Ns Ic \&]
 Interpolate the string with the
 .Ar name .


@@ -1903,10 +1977,22 @@ Left italic correction (groff extension); ignored by
 .Xr mandoc 1 .
 .It Ic \e-
 Special character
 .Xr mandoc 1 .
 .It Ic \e-
 Special character

-.Dq mathematical minus sign .
+.Dq mathematical minus sign ;
+see
+.Xr mandoc_char 7
+for details.

 .It Ic \e/
 Right italic correction (groff extension); ignored by
 .Xr mandoc 1 .
 .It Ic \e/
 Right italic correction (groff extension); ignored by
 .Xr mandoc 1 .

+.It Ic \e:
+Breaking the line is allowed at this point of the word
+without inserting a hyphen.
+.It Ic \e?
+Embed the text up to the next
+.Ic \e?
+into the current diversion without interpreting requests, macros,
+and escapes.
+This is a groff extension and currently unsupported.

 .It Ic \e[ Ns Ar name Ns Ic \&]
 .Sx Special Characters
 with names of arbitrary length, see
 .It Ic \e[ Ns Ar name Ns Ic \&]
 .Sx Special Characters
 with names of arbitrary length, see


@@ -1914,6 +2000,10 @@ with names of arbitrary length, see
 .It Ic \e^
 One-twelfth em half-narrow space character, effectively zero-width in
 .Xr mandoc 1 .
 .It Ic \e^
 One-twelfth em half-narrow space character, effectively zero-width in
 .Xr mandoc 1 .

+.It Ic \e_
+Underline special character; use
+.Ic \e(ul
+instead.

 .It Ic \e`
 Grave accent special character; use
 .Ic \e(ga
 .It Ic \e`
 Grave accent special character; use
 .Ic \e(ga


@@ -1934,6 +2024,9 @@ Digit width space character.
 .It Ic \eA\(aq Ns Ar string Ns Ic \(aq
 Anchor definition; ignored by
 .Xr mandoc 1 .
 .It Ic \eA\(aq Ns Ar string Ns Ic \(aq
 Anchor definition; ignored by
 .Xr mandoc 1 .

+.It Ic \ea
+Leader character; ignored by
+.Xr mandoc 1 .

 .It Ic \eB\(aq Ns Ar string Ns Ic \(aq
 Interpolate
 .Sq 1
 .It Ic \eB\(aq Ns Ar string Ns Ic \(aq
 Interpolate
 .Sq 1


@@ -1941,7 +2034,7 @@ if
 .Ar string
 conforms to the syntax of
 .Sx Numerical expressions
 .Ar string
 conforms to the syntax of
 .Sx Numerical expressions

-explained above and
+explained above or

 .Sq 0
 otherwise.
 .It Ic \eb\(aq Ns Ar string Ns Ic \(aq
 .Sq 0
 otherwise.
 .It Ic \eb\(aq Ns Ar string Ns Ic \(aq


@@ -1961,6 +2054,13 @@ Draw graphics function; ignored by
 .It Ic \ed
 Move down by half a line; ignored by
 .Xr mandoc 1 .
 .It Ic \ed
 Move down by half a line; ignored by
 .Xr mandoc 1 .

+.It Ic \eE
+Escape character intended to not be interpreted in copy mode.
+In
+.Xr mandoc 1 ,
+it currently does the same as
+.Ic \e
+itself.

 .It Ic \ee
 Backslash special character.
 .It Ic \eF[ Ns Ar name Ns Ic \&]
 .It Ic \ee
 Backslash special character.
 .It Ic \eF[ Ns Ar name Ns Ic \&]


@@ -1974,11 +2074,15 @@ and
 Switch to the font
 .Ar name ,
 see
 Switch to the font
 .Ar name ,
 see

-.Sx Text Decoration .
+.Sx Font Selection .

 For short names, there are variants
 .Ic \ef Ns Ar c
 and
 .Ic \ef( Ns Ar cc .
 For short names, there are variants
 .Ic \ef Ns Ar c
 and
 .Ic \ef( Ns Ar cc .

+An empty name
+.Ic \ef[]
+defaults to
+.Ic \efP .

 .It Ic \eg[ Ns Ar name Ns Ic \&]
 Interpolate the format of a number register; ignored by
 .Xr mandoc 1 .
 .It Ic \eg[ Ns Ar name Ns Ic \&]
 Interpolate the format of a number register; ignored by
 .Xr mandoc 1 .


@@ -2042,6 +2146,14 @@ the register is first incremented or decremented by the
 that was specified in the relevant
 .Ic \&nr
 request, and the changed value is interpolated.
 that was specified in the relevant
 .Ic \&nr
 request, and the changed value is interpolated.

+.It Ic \eO Ns Ar digit , Ic \eO[5 Ns arguments Ns Ic \&]
+Suppress output.
+This is a groff extension and currently unsupported.
+With an argument of
+.Ic 1 , 2 , 3 ,
+or
+.Ic 4 ,
+it is ignored.

 .It Ic \eo\(aq Ns Ar string Ns Ic \(aq
 Overstrike, writing all the characters contained in the
 .Ar string
 .It Ic \eo\(aq Ns Ar string Ns Ic \(aq
 Overstrike, writing all the characters contained in the
 .Ar string


@@ -2053,6 +2165,9 @@ Break the output line at the end of the current word.
 .It Ic \eR\(aq Ns Ar name Oo +|- Oc Ns Ar number Ns Ic \(aq
 Set number register; ignored by
 .Xr mandoc 1 .
 .It Ic \eR\(aq Ns Ar name Oo +|- Oc Ns Ar number Ns Ic \(aq
 Set number register; ignored by
 .Xr mandoc 1 .

+.It Ic \er
+Move up by one line; ignored by
+.Xr mandoc 1 .

 .It Ic \eS\(aq Ns Ar number Ns Ic \(aq
 Slant output; ignored by
 .Xr mandoc 1 .
 .It Ic \eS\(aq Ns Ar number Ns Ic \(aq
 Slant output; ignored by
 .Xr mandoc 1 .


@@ -2169,7 +2284,7 @@ code.
 .Pp
 The special semantics of the
 .Cm nS
 .Pp
 The special semantics of the
 .Cm nS

-number register is an idiosyncracy of
+number register is an idiosyncrasy of

 .Ox
 manuals and not supported by other
 .Xr mdoc 7
 .Ox
 manuals and not supported by other
 .Xr mdoc 7


@@ -2216,7 +2331,7 @@ for
 .At v2 ,
 then ported nroff to C as troff, which Brian W. Kernighan released with
 .At v7 .
 .At v2 ,
 then ported nroff to C as troff, which Brian W. Kernighan released with
 .At v7 .

-In 1989, James Clarke re-implemented troff in C++, naming it groff.
+In 1989, James Clark re-implemented troff in C++, naming it groff.

 .Sh AUTHORS
 .An -nosplit
 This
 .Sh AUTHORS
 .An -nosplit
 This