Warn about missing mlinks.

[mandoc.git] / mandoc_char.7

diff --git a/mandoc_char.7 b/mandoc_char.7
index 1d90fc69145a897af1c450357ba48e332e733309..8d8356652ef5bdd876b00ccbed86fb1120f74371 100644 (file)
--- a/mandoc_char.7
+++ b/mandoc_char.7
@@ -1,6 +1,8 @@
-.\"    $Id: mandoc_char.7,v 1.8 2009/07/26 19:53:40 kristaps Exp $
+.\"    $Id: mandoc_char.7,v 1.56 2013/12/26 17:23:42 schwarze Exp $

 .\"
 .\"

-.\" Copyright (c) 2009 Kristaps Dzonsons <kristaps@kth.se>
+.\" Copyright (c) 2003 Jason McIntyre <jmc@openbsd.org>
+.\" Copyright (c) 2009, 2010, 2011 Kristaps Dzonsons <kristaps@bsd.lv>
+.\" Copyright (c) 2011 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


@@ -13,484 +15,733 @@
 .\" 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.
 .\" 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 26 2009 $
+.\"
+.Dd $Mdocdate: December 26 2013 $

 .Dt MANDOC_CHAR 7
 .Os
 .Dt MANDOC_CHAR 7
 .Os

-.\" SECTION

 .Sh NAME
 .Nm mandoc_char
 .Nd mandoc special characters
 .Sh NAME
 .Nm mandoc_char
 .Nd mandoc special characters

-.\" SECTION

 .Sh DESCRIPTION
 .Sh DESCRIPTION

-This documents the special characters accepted by 
+This page documents the
+.Xr roff 7
+escape sequences accepted by

 .Xr mandoc 1
 .Xr mandoc 1

-to format
+to represent special characters in

 .Xr mdoc 7
 and
 .Xr man 7
 .Xr mdoc 7
 and
 .Xr man 7

-documents.  Specific output devices of
-.Xr mandoc 1 ,
-dictated by the
-.Fl T Ns Ar output
-argument, will properly render these sequences.
+documents.

 .Pp
 .Pp

-Both
-.Xr mdoc 7
+The rendering depends on the
+.Xr mandoc 1
+output mode; in ASCII output, most characters are completely
+unintelligible.
+For that reason, using any of the special characters documented here,
+except those discussed in the
+.Sx DESCRIPTION ,
+is strongly discouraged; they are supported merely for backwards
+compatibility with existing documents.
+.Pp
+In particular, in English manual pages, do not use special-character
+escape sequences to represent national language characters in author
+names; instead, provide ASCII transcriptions of the names.
+.Ss Dashes and Hyphens
+In typography there are different types of dashes of various width:
+the hyphen (-),
+the minus sign (\-),
+the en-dash (\(en),
+and the em-dash (\(em).
+.Pp
+Hyphens are used for adjectives;
+to separate the two parts of a compound word;
+or to separate a word across two successive lines of text.
+The hyphen does not need to be escaped:
+.Bd -unfilled -offset indent
+blue-eyed
+lorry-driver
+.Ed
+.Pp
+The mathematical minus sign is used for negative numbers or subtraction.
+It should be written as
+.Sq \e- :
+.Bd -unfilled -offset indent
+a = 3 \e- 1;
+b = \e-2;
+.Ed
+.Pp
+The en-dash is used to separate the two elements of a range,
+or can be used the same way as an em-dash.
+It should be written as
+.Sq \e(en :
+.Bd -unfilled -offset indent
+pp. 95\e(en97.
+Go away \e(en or else!
+.Ed
+.Pp
+The em-dash can be used to show an interruption
+or can be used the same way as colons, semi-colons, or parentheses.
+It should be written as
+.Sq \e(em :
+.Bd -unfilled -offset indent
+Three things \e(em apples, oranges, and bananas.
+This is not that \e(em rather, this is that.
+.Ed
+.Pp
+Note:
+hyphens, minus signs, and en-dashes look identical under normal ASCII output.
+Other formats, such as PostScript, render them correctly,
+with differing widths.
+.Ss Spaces
+To separate words in normal text, for indenting and alignment
+in literal context, and when none of the following special cases apply,
+just use the normal space character
+.Pq Sq \  .
+.Pp
+When filling text, output lines may be broken between words, i.e. at space
+characters.
+To prevent a line break between two particular words,
+use the unpaddable non-breaking space escape sequence
+.Pq Sq \e\ \&
+instead of the normal space character.
+For example, the input string
+.Dq number\e\ 1
+will be kept together as
+.Dq number\ 1
+on the same output line.
+.Pp
+On request and macro lines, the normal space character serves as an
+argument delimiter.
+To include whitespace into arguments, quoting is usually the best choice;
+see the MACRO SYNTAX section in
+.Xr roff 7 .
+In some cases, using the non-breaking space escape sequence
+.Pq Sq \e\ \&
+may be preferable.
+.Pp
+To escape macro names and to protect whitespace at the end
+of input lines, the zero-width space
+.Pq Sq \e&
+is often useful.
+For example, in
+.Xr mdoc 7 ,
+a normal space character can be displayed in single quotes in either
+of the following ways:
+.Pp
+.Dl .Sq \(dq \(dq
+.Dl .Sq \e \e&
+.Ss Quotes
+On request and macro lines, the double-quote character
+.Pq Sq \(dq
+is handled specially to allow quoting.
+One way to prevent this special handling is by using the
+.Sq \e(dq
+escape sequence.
+.Pp
+Note that on text lines, literal double-quote characters can be used
+verbatim.
+All other quote-like characters can be used verbatim as well,
+even on request and macro lines.
+.Ss Periods
+The period
+.Pq Sq \&.
+is handled specially at the beginning of an input line,
+where it introduces a
+.Xr roff 7
+request or a macro, and when appearing alone as a macro argument in
+.Xr mdoc 7 .
+In such situations, prepend a zero-width space
+.Pq Sq \e&.
+to make it behave like normal text.
+.Pp
+Do not use the
+.Sq \e.
+escape sequence.
+It does not prevent special handling of the period.
+.Ss Backslashes
+To include a literal backslash
+.Pq Sq \e
+into the output, use the
+.Pq Sq \ee
+escape sequence.
+.Pp
+Note that doubling it
+.Pq Sq \e\e
+is not the right way to output a backslash.
+Because
+.Xr mandoc 1
+does not implement full
+.Xr roff 7
+functionality, it may work with
+.Xr mandoc 1 ,
+but it may have weird effects on complete
+.Xr roff 7
+implementations.
+.Sh SPECIAL CHARACTERS
+Special characters are encoded as
+.Sq \eX
+.Pq for a one-character escape ,
+.Sq \e(XX
+.Pq two-character ,

 and
 and

-.Xr man 7
-encode special characters with slightly different semantics; consult the
-respective manuals for these escapes.
-.\" PARAGRAPH
-.Pp
-Typographic:
-.Bl -tag -width Ds -offset indent -compact
-.It \e~
-.Pq non-breaking space
-.It \e
-.Pq space
-.It \e^
-.Pq zero-width space
-.It \e^
-.Pq zero-width space
-.It \e&
-.Pq zero-width space
+.Sq \e[N]
+.Pq N-character .
+For details, see the
+.Em Special Characters
+subsection of the
+.Xr roff 7
+manual.
+.Pp
+Spacing:
+.Bl -column "Input" "Description" -offset indent -compact
+.It Em Input Ta Em Description
+.It Sq \e\ \& Ta unpaddable non-breaking space
+.It \e~      Ta paddable non-breaking space
+.It \e0      Ta unpaddable, breaking digit-width space
+.It \e|      Ta one-sixth \e(em narrow space, zero width in nroff mode
+.It \e^      Ta one-twelfth \e(em half-narrow space, zero width in nroff
+.It \e&      Ta zero-width space
+.It \e%      Ta zero-width space allowing hyphenation

 .El
 .El

-.\" PARAGRAPH
-.Pp
-Grammatic:
-.Bl -tag -width Ds -offset indent -compact
-.It \e(em
-.Pq em-dash
-.It \e(en
-.Pq en-dash
-.It \e(hy
-.Pq hyphen
-.It \e\e
-.Pq back-slash
-.It \e'
-.Pq apostrophe
-.It \e`
-.Pq back-tick
-.It \e.
-.Pq period
-.It \e(r!
-.Pq upside-down exclamation
-.It \e(r?
-.Pq upside-down question
+.Pp
+Lines:
+.Bl -column "Input" "Rendered" "Description" -offset indent -compact
+.It Em Input Ta Em Rendered Ta Em Description
+.It \e(ba    Ta \(ba        Ta bar
+.It \e(br    Ta \(br        Ta box rule
+.It \e(ul    Ta \(ul        Ta underscore
+.It \e(rl    Ta \(rl        Ta overline
+.It \e(bb    Ta \(bb        Ta broken bar
+.It \e(sl    Ta \(sl        Ta forward slash
+.It \e(rs    Ta \(rs        Ta backward slash

 .El
 .El

-.\" PARAGRAPH
-.Pp
-Enclosures:
-.Bl -tag -width Ds -offset indent -compact
-.It \e(lh
-.Pq left hand
-.It \e(rh
-.Pq right hand
-.It \e(Fo
-.Pq left guillemet
-.It \e(Fc
-.Pq right guillemet
-.It \e(fo
-.Pq left guilsing
-.It \e(fc
-.Pq right guilsing
-.It \e(rC
-.Pq right brace
-.It \e(lC
-.Pq left brace
-.It \e(ra
-.Pq right angle
-.It \e(la
-.Pq left angle
-.It \e(rB
-.Pq right bracket
-.It \e(lB
-.Pq left bracket
-.It \eq
-.Pq double-quote
-.It \e(lq
-.Pq left double-quote
-.It \e(Lq
-.Pq left double-quote, deprecated
-.It \e(rq
-.Pq right double-quote
-.It \e(Rq
-.Pq right double-quote, deprecated
-.It \e(oq
-.Pq left single-quote
-.It \e(aq
-.Pq right single-quote
-.It \e(Bq
-.Pq right low double-quote
-.It \e(bq
-.Pq right low single-quote
+.Pp
+Text markers:
+.Bl -column "Input" "Rendered" "Description" -offset indent -compact
+.It Em Input Ta Em Rendered Ta Em Description
+.It \e(ci    Ta \(ci        Ta circle
+.It \e(bu    Ta \(bu        Ta bullet
+.It \e(dd    Ta \(dd        Ta double dagger
+.It \e(dg    Ta \(dg        Ta dagger
+.It \e(lz    Ta \(lz        Ta lozenge
+.It \e(sq    Ta \(sq        Ta white square
+.It \e(ps    Ta \(ps        Ta paragraph
+.It \e(sc    Ta \(sc        Ta section
+.It \e(lh    Ta \(lh        Ta left hand
+.It \e(rh    Ta \(rh        Ta right hand
+.It \e(at    Ta \(at        Ta at
+.It \e(sh    Ta \(sh        Ta hash (pound)
+.It \e(CR    Ta \(CR        Ta carriage return
+.It \e(OK    Ta \(OK        Ta check mark

 .El
 .El

-.\" PARAGRAPH
-.Pp
-Indicatives:
-.Bl -tag -width Ds -offset indent -compact
-.It \e(<-
-.Pq left arrow
-.It \e(->
-.Pq right arrow
-.It \e(ua
-.Pq up arrow
-.It \e(da
-.Pq down arrow
-.It \e(<>
-.Pq left-right arrow
-.It \e(lA
-.Pq left double-arrow
-.It \e(rA
-.Pq right double-arrow
-.It \e(uA
-.Pq up double-arrow
-.It \e(dA
-.Pq down double-arrow
-.It \e(hA
-.Pq left-right double-arrow
+.Pp
+Legal symbols:
+.Bl -column "Input" "Rendered" "Description" -offset indent -compact
+.It Em Input Ta Em Rendered Ta Em Description
+.It \e(co    Ta \(co        Ta copyright
+.It \e(rg    Ta \(rg        Ta registered
+.It \e(tm    Ta \(tm        Ta trademarked
+.El
+.Pp
+Punctuation:
+.Bl -column "Input" "Rendered" "Description" -offset indent -compact
+.It Em Input Ta Em Rendered Ta Em Description
+.It \e(em    Ta \(em        Ta em-dash
+.It \e(en    Ta \(en        Ta en-dash
+.It \e(hy    Ta \(hy        Ta hyphen
+.It \ee      Ta \e          Ta back-slash
+.It \e.      Ta \.          Ta period
+.It \e(r!    Ta \(r!        Ta upside-down exclamation
+.It \e(r?    Ta \(r?        Ta upside-down question
+.El
+.Pp
+Quotes:
+.Bl -column "Input" "Rendered" "Description" -offset indent -compact
+.It Em Input Ta Em Rendered Ta Em Description
+.It \e(Bq    Ta \(Bq        Ta right low double-quote
+.It \e(bq    Ta \(bq        Ta right low single-quote
+.It \e(lq    Ta \(lq        Ta left double-quote
+.It \e(rq    Ta \(rq        Ta right double-quote
+.It \e(oq    Ta \(oq        Ta left single-quote
+.It \e(cq    Ta \(cq        Ta right single-quote
+.It \e(aq    Ta \(aq        Ta apostrophe quote (text)
+.It \e(dq    Ta \(dq        Ta double quote (text)
+.It \e(Fo    Ta \(Fo        Ta left guillemet
+.It \e(Fc    Ta \(Fc        Ta right guillemet
+.It \e(fo    Ta \(fo        Ta left single guillemet
+.It \e(fc    Ta \(fc        Ta right single guillemet
+.El
+.Pp
+Brackets:
+.Bl -column "xxbracketrightbpx" Rendered Description -offset indent -compact
+.It Em Input Ta Em Rendered Ta Em Description
+.It \e(lB    Ta \(lB        Ta left bracket
+.It \e(rB    Ta \(rB        Ta right bracket
+.It \e(lC    Ta \(lC        Ta left brace
+.It \e(rC    Ta \(rC        Ta right brace
+.It \e(la    Ta \(la        Ta left angle
+.It \e(ra    Ta \(ra        Ta right angle
+.It \e(bv    Ta \(bv        Ta brace extension
+.It \e[braceex] Ta \[braceex] Ta brace extension
+.It \e[bracketlefttp] Ta \[bracketlefttp] Ta top-left hooked bracket
+.It \e[bracketleftbp] Ta \[bracketleftbp] Ta bottom-left hooked bracket
+.It \e[bracketleftex] Ta \[bracketleftex] Ta left hooked bracket extension
+.It \e[bracketrighttp] Ta \[bracketrighttp] Ta top-right hooked bracket
+.It \e[bracketrightbp] Ta \[bracketrightbp] Ta bottom-right hooked bracket
+.It \e[bracketrightex] Ta \[bracketrightex] Ta right hooked bracket extension
+.It \e(lt    Ta \(lt        Ta top-left hooked brace
+.It \e[bracelefttp] Ta \[bracelefttp] Ta top-left hooked brace
+.It \e(lk    Ta \(lk        Ta mid-left hooked brace
+.It \e[braceleftmid] Ta \[braceleftmid] Ta mid-left hooked brace
+.It \e(lb    Ta \(lb        Ta bottom-left hooked brace
+.It \e[braceleftbp] Ta \[braceleftbp] Ta bottom-left hooked brace
+.It \e[braceleftex] Ta \[braceleftex] Ta left hooked brace extension
+.It \e(rt    Ta \(rt        Ta top-left hooked brace
+.It \e[bracerighttp] Ta \[bracerighttp] Ta top-right hooked brace
+.It \e(rk    Ta \(rk        Ta mid-right hooked brace
+.It \e[bracerightmid] Ta \[bracerightmid] Ta mid-right hooked brace
+.It \e(rb    Ta \(rb        Ta bottom-right hooked brace
+.It \e[bracerightbp] Ta \[bracerightbp] Ta bottom-right hooked brace
+.It \e[bracerightex] Ta \[bracerightex] Ta right hooked brace extension
+.It \e[parenlefttp] Ta \[parenlefttp] Ta top-left hooked parenthesis
+.It \e[parenleftbp] Ta \[parenleftbp] Ta bottom-left hooked parenthesis
+.It \e[parenleftex] Ta \[parenleftex] Ta left hooked parenthesis extension
+.It \e[parenrighttp] Ta \[parenrighttp] Ta top-right hooked parenthesis
+.It \e[parenrightbp] Ta \[parenrightbp] Ta bottom-right hooked parenthesis
+.It \e[parenrightex] Ta \[parenrightex] Ta right hooked parenthesis extension
+.El
+.Pp
+Arrows:
+.Bl -column "Input" "Rendered" "Description" -offset indent -compact
+.It Em Input Ta Em Rendered Ta Em Description
+.It \e(<-    Ta \(<-        Ta left arrow
+.It \e(->    Ta \(->        Ta right arrow
+.It \e(<>    Ta \(<>        Ta left-right arrow
+.It \e(da    Ta \(da        Ta down arrow
+.It \e(ua    Ta \(ua        Ta up arrow
+.It \e(va    Ta \(va        Ta up-down arrow
+.It \e(lA    Ta \(lA        Ta left double-arrow
+.It \e(rA    Ta \(rA        Ta right double-arrow
+.It \e(hA    Ta \(hA        Ta left-right double-arrow
+.It \e(uA    Ta \(uA        Ta up double-arrow
+.It \e(dA    Ta \(dA        Ta down double-arrow
+.It \e(vA    Ta \(vA        Ta up-down double-arrow
+.El
+.Pp
+Logical:
+.Bl -column "Input" "Rendered" "Description" -offset indent -compact
+.It Em Input Ta Em Rendered Ta Em Description
+.It \e(AN    Ta \(AN        Ta logical and
+.It \e(OR    Ta \(OR        Ta logical or
+.It \e(no    Ta \(no        Ta logical not
+.It \e[tno]  Ta \[tno]      Ta logical not (text)
+.It \e(te    Ta \(te        Ta existential quantifier
+.It \e(fa    Ta \(fa        Ta universal quantifier
+.It \e(st    Ta \(st        Ta such that
+.It \e(tf    Ta \(tf        Ta therefore
+.It \e(3d    Ta \(3d        Ta therefore
+.It \e(or    Ta \(or        Ta bitwise or

 .El
 .El

-.\" PARAGRAPH

 .Pp
 Mathematical:
 .Pp
 Mathematical:

-.Bl -tag -width Ds -offset indent -compact
-.It \e(es
-.Pq empty set
-.It \e(ca
-.Pq intersection
-.It \e(cu
-.Pq union
-.It \e(gr
-.Pq gradient
-.It \e(pd
-.Pq partial differential
-.It \e(ap
-.Pq similarity
-.It \e(=)
-.Pq proper superset
-.It \e((=
-.Pq proper subset
-.It \e(eq
-.Pq equals
-.It \e(di
-.Pq division
-.It \e(mu
-.Pq multiplication
-.It \e(pl
-.Pq addition
-.It \e-
-.Pq subtraction
-.It \e(nm
-.Pq not element
-.It \e(mo
-.Pq element
-.It \e(Im
-.Pq imaginary
-.It \e(Re
-.Pq real
-.It \e(Ah
-.Pq aleph
-.It \e(te
-.Pq existential quantifier
-.It \e(fa
-.Pq universal quantifier
-.It \e(AN
-.Pq logical AND
-.It \e(OR
-.Pq logical OR
-.It \e(no
-.Pq logical NOT
-.It \e(st
-.Pq such that
-.It \e(tf
-.Pq therefore
-.It \e(~~
-.Pq approximate
-.It \e(~=
-.Pq approximately equals
-.It \e(=~
-.Pq congruent
-.It \e(Gt
-.Pq greater-than, deprecated
-.It \e(Lt
-.Pq less-than, deprecated
-.It \e(<=
-.Pq less-than-equal
-.It \e(Le
-.Pq less-than-equal, deprecated
-.It \e(>=
-.Pq greater-than-equal
-.It \e(Ge
-.Pq greater-than-equal
-.It \e(==
-.Pq equal
-.It \e(!=
-.Pq not equal
-.It \e(Ne
-.Pq not equal, deprecated
-.It \e(if
-.Pq infinity
-.It \e(If
-.Pq infinity, deprecated
-.It \e(na
-.Pq NaN , an extension
-.It \e(Na
-.Pq NaN, deprecated
-.It \e(+-
-.Pq plus-minus
-.It \e(Pm
-.Pq plus-minus, deprecated
-.It \e(**
-.Pq asterisk
+.Bl -column "xxcoproductxx" "Rendered" "Description" -offset indent -compact
+.It Em Input Ta Em Rendered Ta Em Description
+.It \e(pl    Ta \(pl        Ta plus
+.It \e(mi    Ta \(mi        Ta minus
+.It \e-      Ta \-          Ta minus (text)
+.It \e(-+    Ta \(-+        Ta minus-plus
+.It \e(+-    Ta \(+-        Ta plus-minus
+.It \e[t+-]  Ta \[t+-]      Ta plus-minus (text)
+.It \e(pc    Ta \(pc        Ta centre-dot
+.It \e(mu    Ta \(mu        Ta multiply
+.It \e[tmu]  Ta \[tmu]      Ta multiply (text)
+.It \e(c*    Ta \(c*        Ta circle-multiply
+.It \e(c+    Ta \(c+        Ta circle-plus
+.It \e(di    Ta \(di        Ta divide
+.It \e[tdi]  Ta \[tdi]      Ta divide (text)
+.It \e(f/    Ta \(f/        Ta fraction
+.It \e(**    Ta \(**        Ta asterisk
+.It \e(<=    Ta \(<=        Ta less-than-equal
+.It \e(>=    Ta \(>=        Ta greater-than-equal
+.It \e(<<    Ta \(<<        Ta much less
+.It \e(>>    Ta \(>>        Ta much greater
+.It \e(eq    Ta \(eq        Ta equal
+.It \e(!=    Ta \(!=        Ta not equal
+.It \e(==    Ta \(==        Ta equivalent
+.It \e(ne    Ta \(ne        Ta not equivalent
+.It \e(=~    Ta \(=~        Ta congruent
+.It \e(-~    Ta \(-~        Ta asymptotically congruent
+.It \e(ap    Ta \(ap        Ta asymptotically similar
+.It \e(~~    Ta \(~~        Ta approximately similar
+.It \e(~=    Ta \(~=        Ta approximately equal
+.It \e(pt    Ta \(pt        Ta proportionate
+.It \e(es    Ta \(es        Ta empty set
+.It \e(mo    Ta \(mo        Ta element
+.It \e(nm    Ta \(nm        Ta not element
+.It \e(sb    Ta \(sb        Ta proper subset
+.It \e(nb    Ta \(nb        Ta not subset
+.It \e(sp    Ta \(sp        Ta proper superset
+.It \e(nc    Ta \(nc        Ta not superset
+.It \e(ib    Ta \(ib        Ta reflexive subset
+.It \e(ip    Ta \(ip        Ta reflexive superset
+.It \e(ca    Ta \(ca        Ta intersection
+.It \e(cu    Ta \(cu        Ta union
+.It \e(/_    Ta \(/_        Ta angle
+.It \e(pp    Ta \(pp        Ta perpendicular
+.It \e(is    Ta \(is        Ta integral
+.It \e[integral] Ta \[integral] Ta integral
+.It \e[sum]    Ta \[sum]   Ta summation
+.It \e[product] Ta \[product] Ta product
+.It \e[coproduct] Ta \[coproduct] Ta coproduct
+.It \e(gr    Ta \(gr        Ta gradient
+.It \e(sr    Ta \(sr        Ta square root
+.It \e[sqrt] Ta \[sqrt]     Ta square root
+.It \e(lc    Ta \(lc        Ta left-ceiling
+.It \e(rc    Ta \(rc        Ta right-ceiling
+.It \e(lf    Ta \(lf        Ta left-floor
+.It \e(rf    Ta \(rf        Ta right-floor
+.It \e(if    Ta \(if        Ta infinity
+.It \e(Ah    Ta \(Ah        Ta aleph
+.It \e(Im    Ta \(Im        Ta imaginary
+.It \e(Re    Ta \(Re        Ta real
+.It \e(pd    Ta \(pd        Ta partial differential
+.It \e(-h    Ta \(-h        Ta Planck constant over 2\(*p
+.It \e[12]   Ta \[12]       Ta one-half
+.It \e[14]   Ta \[14]       Ta one-fourth
+.It \e[34]   Ta \[34]       Ta three-fourths

 .El
 .El

-.\" PARAGRAPH

 .Pp
 Ligatures:
 .Pp
 Ligatures:

-.Bl -tag -width Ds -offset indent -compact
-.It \e(ss
-.Pq German eszett
-.It \e(AE
-.Pq upper-case AE
-.It \e(ae
-.Pq lower-case AE
-.It \e(OE
-.Pq upper-case OE
-.It \e(oe
-.Pq lower-case OE
-.It \e(ff
-.Pq ff ligature
-.It \e(fi
-.Pq fi ligature
-.It \e(fl
-.Pq fl ligature
-.It \e(Fi
-.Pq ffi ligature
-.It \e(Fl
-.Pq ffl ligature
+.Bl -column "Input" "Rendered" "Description" -offset indent -compact
+.It Em Input Ta Em Rendered Ta Em Description
+.It \e(ff    Ta \(ff        Ta ff ligature
+.It \e(fi    Ta \(fi        Ta fi ligature
+.It \e(fl    Ta \(fl        Ta fl ligature
+.It \e(Fi    Ta \(Fi        Ta ffi ligature
+.It \e(Fl    Ta \(Fl        Ta ffl ligature
+.It \e(AE    Ta \(AE        Ta AE
+.It \e(ae    Ta \(ae        Ta ae
+.It \e(OE    Ta \(OE        Ta OE
+.It \e(oe    Ta \(oe        Ta oe
+.It \e(ss    Ta \(ss        Ta German eszett
+.It \e(IJ    Ta \(IJ        Ta IJ ligature
+.It \e(ij    Ta \(ij        Ta ij ligature

 .El
 .El

-.\" PARAGRAPH
-.Pp
-Diacritics and letters:
-.Bl -tag -width Ds -offset indent -compact
-.It \e(ga
-.Pq grave accent
-.It \e(aa
-.Pq accute accent
-.It \e(a"
-.Pq umlaut accent
-.It \e(ad
-.Pq dieresis accent
-.It \e(a~
-.Pq tilde accent
-.It \e(a^
-.Pq circumflex accent
-.It \e(ac
-.Pq cedilla accent
-.It \e(ad
-.Pq dieresis accent
-.It \e(ah
-.Pq caron accent
-.It \e(ao
-.Pq ring accent
-.It \e(ho
-.Pq hook accent
-.It \e(ab
-.Pq breve accent
-.It \e(a-
-.Pq macron accent
-.It \e(-D
-.Pq upper-case eth
-.It \e(Sd
-.Pq lower-case eth
-.It \e(TP
-.Pq upper-case thorn
-.It \e(Tp
-.Pq lower-case thorn
-.It \e('A
-.Pq upper-case acute A
-.It \e('E
-.Pq upper-case acute E
-.It \e('I
-.Pq upper-case acute I
-.It \e('O
-.Pq upper-case acute O
-.It \e('U
-.Pq upper-case acute U
-.It \e('a
-.Pq lower-case acute a
-.It \e('e
-.Pq lower-case acute e
-.It \e('i
-.Pq lower-case acute i
-.It \e('o
-.Pq lower-case acute o
-.It \e('u
-.Pq lower-case acute u
-.It \e(`A
-.Pq upper-case grave A
-.It \e(`E
-.Pq upper-case grave E
-.It \e(`I
-.Pq upper-case grave I
-.It \e(`O
-.Pq upper-case grave O
-.It \e(`U
-.Pq upper-case grave U
-.It \e(`a
-.Pq lower-case grave a
-.It \e(`e
-.Pq lower-case grave e
-.It \e(`i
-.Pq lower-case grave i
-.It \e(`o
-.Pq lower-case grave o
-.It \e(`u
-.Pq lower-case grave u
-.It \e(~A
-.Pq upper-case tilde A
-.It \e(~N
-.Pq upper-case tilde N
-.It \e(~O
-.Pq upper-case tilde O
-.It \e(~a
-.Pq lower-case tilde a
-.It \e(~n
-.Pq lower-case tilde n
-.It \e(~o
-.Pq lower-case tilde o
-.It \e(:A
-.Pq upper-case dieresis A
-.It \e(:E
-.Pq upper-case dieresis E
-.It \e(:I
-.Pq upper-case dieresis I
-.It \e(:O
-.Pq upper-case dieresis O
-.It \e(:U
-.Pq upper-case dieresis U
-.It \e(:a
-.Pq lower-case dieresis a
-.It \e(:e
-.Pq lower-case dieresis e
-.It \e(:i
-.Pq lower-case dieresis i
-.It \e(:o
-.Pq lower-case dieresis o
-.It \e(:u
-.Pq lower-case dieresis u
-.It \e(:y
-.Pq lower-case dieresis y
-.It \e(^A
-.Pq upper-case circumflex A
-.It \e(^E
-.Pq upper-case circumflex E
-.It \e(^I
-.Pq upper-case circumflex I
-.It \e(^O
-.Pq upper-case circumflex O
-.It \e(^U
-.Pq upper-case circumflex U
-.It \e(^a
-.Pq lower-case circumflex a
-.It \e(^e
-.Pq lower-case circumflex e
-.It \e(^i
-.Pq lower-case circumflex i
-.It \e(^o
-.Pq lower-case circumflex o
-.It \e(^u
-.Pq lower-case circumflex u
-.It \e(,C
-.Pq upper-case cedilla C
-.It \e(,c
-.Pq lower-case cedilla c
-.It \e(/L
-.Pq upper-case stroke L
-.It \e(/l
-.Pq lower-case stroke l
-.It \e(/O
-.Pq upper-case stroke O
-.It \e(/o
-.Pq lower-case stroke o
-.It \e(oA
-.Pq upper-case ring A
-.It \e(oa
-.Pq lower-case ring a
+.Pp
+Accents:
+.Bl -column "Input" "Rendered" "Description" -offset indent -compact
+.It Em Input Ta Em Rendered Ta Em Description
+.It \e(a"    Ta \(a"        Ta Hungarian umlaut
+.It \e(a-    Ta \(a-        Ta macron
+.It \e(a.    Ta \(a.        Ta dotted
+.It \e(a^    Ta \(a^        Ta circumflex
+.It \e(aa    Ta \(aa        Ta acute
+.It \e'      Ta \'          Ta acute
+.It \e(ga    Ta \(ga        Ta grave
+.It \e`      Ta \`          Ta grave
+.It \e(ab    Ta \(ab        Ta breve
+.It \e(ac    Ta \(ac        Ta cedilla
+.It \e(ad    Ta \(ad        Ta dieresis
+.It \e(ah    Ta \(ah        Ta caron
+.It \e(ao    Ta \(ao        Ta ring
+.It \e(a~    Ta \(a~        Ta tilde
+.It \e(ho    Ta \(ho        Ta ogonek
+.It \e(ha    Ta \(ha        Ta hat (text)
+.It \e(ti    Ta \(ti        Ta tilde (text)
+.El
+.Pp
+Accented letters:
+.Bl -column "Input" "Rendered" "Description" -offset indent -compact
+.It Em Input Ta Em Rendered Ta Em Description
+.It \e('A    Ta \('A        Ta acute A
+.It \e('E    Ta \('E        Ta acute E
+.It \e('I    Ta \('I        Ta acute I
+.It \e('O    Ta \('O        Ta acute O
+.It \e('U    Ta \('U        Ta acute U
+.It \e('a    Ta \('a        Ta acute a
+.It \e('e    Ta \('e        Ta acute e
+.It \e('i    Ta \('i        Ta acute i
+.It \e('o    Ta \('o        Ta acute o
+.It \e('u    Ta \('u        Ta acute u
+.It \e(`A    Ta \(`A        Ta grave A
+.It \e(`E    Ta \(`E        Ta grave E
+.It \e(`I    Ta \(`I        Ta grave I
+.It \e(`O    Ta \(`O        Ta grave O
+.It \e(`U    Ta \(`U        Ta grave U
+.It \e(`a    Ta \(`a        Ta grave a
+.It \e(`e    Ta \(`e        Ta grave e
+.It \e(`i    Ta \(`i        Ta grave i
+.It \e(`o    Ta \(`i        Ta grave o
+.It \e(`u    Ta \(`u        Ta grave u
+.It \e(~A    Ta \(~A        Ta tilde A
+.It \e(~N    Ta \(~N        Ta tilde N
+.It \e(~O    Ta \(~O        Ta tilde O
+.It \e(~a    Ta \(~a        Ta tilde a
+.It \e(~n    Ta \(~n        Ta tilde n
+.It \e(~o    Ta \(~o        Ta tilde o
+.It \e(:A    Ta \(:A        Ta dieresis A
+.It \e(:E    Ta \(:E        Ta dieresis E
+.It \e(:I    Ta \(:I        Ta dieresis I
+.It \e(:O    Ta \(:O        Ta dieresis O
+.It \e(:U    Ta \(:U        Ta dieresis U
+.It \e(:a    Ta \(:a        Ta dieresis a
+.It \e(:e    Ta \(:e        Ta dieresis e
+.It \e(:i    Ta \(:i        Ta dieresis i
+.It \e(:o    Ta \(:o        Ta dieresis o
+.It \e(:u    Ta \(:u        Ta dieresis u
+.It \e(:y    Ta \(:y        Ta dieresis y
+.It \e(^A    Ta \(^A        Ta circumflex A
+.It \e(^E    Ta \(^E        Ta circumflex E
+.It \e(^I    Ta \(^I        Ta circumflex I
+.It \e(^O    Ta \(^O        Ta circumflex O
+.It \e(^U    Ta \(^U        Ta circumflex U
+.It \e(^a    Ta \(^a        Ta circumflex a
+.It \e(^e    Ta \(^e        Ta circumflex e
+.It \e(^i    Ta \(^i        Ta circumflex i
+.It \e(^o    Ta \(^o        Ta circumflex o
+.It \e(^u    Ta \(^u        Ta circumflex u
+.It \e(,C    Ta \(,C        Ta cedilla C
+.It \e(,c    Ta \(,c        Ta cedilla c
+.It \e(/L    Ta \(/L        Ta stroke L
+.It \e(/l    Ta \(/l        Ta stroke l
+.It \e(/O    Ta \(/O        Ta stroke O
+.It \e(/o    Ta \(/o        Ta stroke o
+.It \e(oA    Ta \(oA        Ta ring A
+.It \e(oa    Ta \(oa        Ta ring a

 .El
 .El

-.\" PARAGRAPH
-.Pp
-Monetary:
-.Bl -tag -width Ds -offset indent -compact
-.It \e(Cs
-.Pq Scandinavian
-.It \e(Do
-.Pq dollar
-.It \e(Po
-.Pq pound
-.It \e(Ye
-.Pq yen
-.It \e(Fn
-.Pq florin
-.It \e(ct
-.Pq cent
+.Pp
+Special letters:
+.Bl -column "Input" "Rendered" "Description" -offset indent -compact
+.It Em Input Ta Em Rendered Ta Em Description
+.It \e(-D    Ta \(-D        Ta Eth
+.It \e(Sd    Ta \(Sd        Ta eth
+.It \e(TP    Ta \(TP        Ta Thorn
+.It \e(Tp    Ta \(Tp        Ta thorn
+.It \e(.i    Ta \(.i        Ta dotless i
+.It \e(.j    Ta \(.j        Ta dotless j

 .El
 .El

-.\" PARAGRAPH
-.Pp
-Special symbols:
-.Bl -tag -width Ds -offset indent -compact
-.It \e0
-.Pq white-space
-.It \e(de
-.Pq degree
-.It \e(ps
-.Pq paragraph
-.It \e(sc
-.Pq section
-.It \e(dg
-.Pq dagger
-.It \e(dd
-.Pq double dagger
-.It \e(ci
-.Pq circle
-.It \e(ba
-.Pq bar
-.It \e(bb
-.Pq broken bar
-.It \e(Ba
-.Pq bar, deprecated
-.It \e(co
-.Pq copyright
-.It \e(rg
-.Pq registered
-.It \e(tm
-.Pq trademarked
-.It \e&
-.Pq non-breaking space
-.It \ee
-.Pq escape
-.It \e(Am
-.Pq ampersand, deprecated
-.El 
-.\" SECTION
+.Pp
+Currency:
+.Bl -column "Input" "Rendered" "Description" -offset indent -compact
+.It Em Input Ta Em Rendered Ta Em Description
+.It \e(Do    Ta \(Do        Ta dollar
+.It \e(ct    Ta \(ct        Ta cent
+.It \e(Eu    Ta \(Eu        Ta Euro symbol
+.It \e(eu    Ta \(eu        Ta Euro symbol
+.It \e(Ye    Ta \(Ye        Ta yen
+.It \e(Po    Ta \(Po        Ta pound
+.It \e(Cs    Ta \(Cs        Ta Scandinavian
+.It \e(Fn    Ta \(Fn        Ta florin
+.El
+.Pp
+Units:
+.Bl -column "Input" "Rendered" "Description" -offset indent -compact
+.It Em Input Ta Em Rendered Ta Em Description
+.It \e(de    Ta \(de        Ta degree
+.It \e(%0    Ta \(%0        Ta per-thousand
+.It \e(fm    Ta \(fm        Ta minute
+.It \e(sd    Ta \(sd        Ta second
+.It \e(mc    Ta \(mc        Ta micro
+.El
+.Pp
+Greek letters:
+.Bl -column "Input" "Rendered" "Description" -offset indent -compact
+.It Em Input Ta Em Rendered Ta Em Description
+.It \e(*A    Ta \(*A        Ta Alpha
+.It \e(*B    Ta \(*B        Ta Beta
+.It \e(*G    Ta \(*G        Ta Gamma
+.It \e(*D    Ta \(*D        Ta Delta
+.It \e(*E    Ta \(*E        Ta Epsilon
+.It \e(*Z    Ta \(*Z        Ta Zeta
+.It \e(*Y    Ta \(*Y        Ta Eta
+.It \e(*H    Ta \(*H        Ta Theta
+.It \e(*I    Ta \(*I        Ta Iota
+.It \e(*K    Ta \(*K        Ta Kappa
+.It \e(*L    Ta \(*L        Ta Lambda
+.It \e(*M    Ta \(*M        Ta Mu
+.It \e(*N    Ta \(*N        Ta Nu
+.It \e(*C    Ta \(*C        Ta Xi
+.It \e(*O    Ta \(*O        Ta Omicron
+.It \e(*P    Ta \(*P        Ta Pi
+.It \e(*R    Ta \(*R        Ta Rho
+.It \e(*S    Ta \(*S        Ta Sigma
+.It \e(*T    Ta \(*T        Ta Tau
+.It \e(*U    Ta \(*U        Ta Upsilon
+.It \e(*F    Ta \(*F        Ta Phi
+.It \e(*X    Ta \(*X        Ta Chi
+.It \e(*Q    Ta \(*Q        Ta Psi
+.It \e(*W    Ta \(*W        Ta Omega
+.It \e(*a    Ta \(*a        Ta alpha
+.It \e(*b    Ta \(*b        Ta beta
+.It \e(*g    Ta \(*g        Ta gamma
+.It \e(*d    Ta \(*d        Ta delta
+.It \e(*e    Ta \(*e        Ta epsilon
+.It \e(*z    Ta \(*z        Ta zeta
+.It \e(*y    Ta \(*y        Ta eta
+.It \e(*h    Ta \(*h        Ta theta
+.It \e(*i    Ta \(*i        Ta iota
+.It \e(*k    Ta \(*k        Ta kappa
+.It \e(*l    Ta \(*l        Ta lambda
+.It \e(*m    Ta \(*m        Ta mu
+.It \e(*n    Ta \(*n        Ta nu
+.It \e(*c    Ta \(*c        Ta xi
+.It \e(*o    Ta \(*o        Ta omicron
+.It \e(*p    Ta \(*p        Ta pi
+.It \e(*r    Ta \(*r        Ta rho
+.It \e(*s    Ta \(*s        Ta sigma
+.It \e(*t    Ta \(*t        Ta tau
+.It \e(*u    Ta \(*u        Ta upsilon
+.It \e(*f    Ta \(*f        Ta phi
+.It \e(*x    Ta \(*x        Ta chi
+.It \e(*q    Ta \(*q        Ta psi
+.It \e(*w    Ta \(*w        Ta omega
+.It \e(+h    Ta \(+h        Ta theta variant
+.It \e(+f    Ta \(+f        Ta phi variant
+.It \e(+p    Ta \(+p        Ta pi variant
+.It \e(+e    Ta \(+e        Ta epsilon variant
+.It \e(ts    Ta \(ts        Ta sigma terminal
+.El
+.Sh PREDEFINED STRINGS
+Predefined strings are inherited from the macro packages of historical
+troff implementations.
+They are
+.Em not recommended
+for use, as they differ across implementations.
+Manuals using these predefined strings are almost certainly not
+portable.
+.Pp
+Their syntax is similar to special characters, using
+.Sq \e*X
+.Pq for a one-character escape ,
+.Sq \e*(XX
+.Pq two-character ,
+and
+.Sq \e*[N]
+.Pq N-character .
+For details, see the
+.Em Predefined Strings
+subsection of the
+.Xr roff 7
+manual.
+.Bl -column "Input" "Rendered" "Description" -offset indent
+.It Em Input Ta Em Rendered Ta Em Description
+.It \e*(Ba   Ta \*(Ba       Ta vertical bar
+.It \e*(Ne   Ta \*(Ne       Ta not equal
+.It \e*(Ge   Ta \*(Ge       Ta greater-than-equal
+.It \e*(Le   Ta \*(Le       Ta less-than-equal
+.It \e*(Gt   Ta \*(Gt       Ta greater-than
+.It \e*(Lt   Ta \*(Lt       Ta less-than
+.It \e*(Pm   Ta \*(Pm       Ta plus-minus
+.It \e*(If   Ta \*(If       Ta infinity
+.It \e*(Pi   Ta \*(Pi       Ta pi
+.It \e*(Na   Ta \*(Na       Ta NaN
+.It \e*(Am   Ta \*(Am       Ta ampersand
+.It \e*R     Ta \*R         Ta restricted mark
+.It \e*(Tm   Ta \*(Tm       Ta trade mark
+.It \e*q     Ta \*q         Ta double-quote
+.It \e*(Rq   Ta \*(Rq       Ta right-double-quote
+.It \e*(Lq   Ta \*(Lq       Ta left-double-quote
+.It \e*(lp   Ta \*(lp       Ta right-parenthesis
+.It \e*(rp   Ta \*(rp       Ta left-parenthesis
+.It \e*(lq   Ta \*(lq       Ta left double-quote
+.It \e*(rq   Ta \*(rq       Ta right double-quote
+.It \e*(ua   Ta \*(ua       Ta up arrow
+.It \e*(va   Ta \*(va       Ta up-down arrow
+.It \e*(<=   Ta \*(<=       Ta less-than-equal
+.It \e*(>=   Ta \*(>=       Ta greater-than-equal
+.It \e*(aa   Ta \*(aa       Ta acute
+.It \e*(ga   Ta \*(ga       Ta grave
+.It \e*(Px   Ta \*(Px       Ta POSIX standard name
+.It \e*(Ai   Ta \*(Ai       Ta ANSI standard name
+.El
+.Sh UNICODE CHARACTERS
+The escape sequences
+.Pp
+.Dl \e[uXXXX] and \eC'uXXXX'
+.Pp
+are interpreted as Unicode codepoints.
+The codepoint must be in the range above U+0080 and less than U+10FFFF.
+For compatibility, the hexadecimal digits
+.Sq A
+to
+.Sq F
+must be given as uppercase characters,
+and points must be zero-padded to four characters; if
+greater than four characters, no zero padding is allowed.
+Unicode surrogates are not allowed.
+.\" .Pp
+.\" Unicode glyphs attenuate to the
+.\" .Sq \&?
+.\" character if invalid or not rendered by current output media.
+.Sh NUMBERED CHARACTERS
+For backward compatibility with existing manuals,
+.Xr mandoc 1
+also supports the
+.Pp
+.Dl \eN\(aq Ns Ar number Ns \(aq
+.Pp
+escape sequence, inserting the character
+.Ar number
+from the current character set into the output.
+Of course, this is inherently non-portable and is already marked
+as deprecated in the Heirloom roff manual.
+For example, do not use \eN'34', use \e(dq, or even the plain
+.Sq \(dq
+character where possible.

 .Sh COMPATIBILITY
 .Sh COMPATIBILITY

-This section documents compatibility of
-.Nm
-with older or existing versions of
-.Xr groff 1 :
-.Pp
-.Bl -tag -width Ds -offset indent -compact
-.It \e(ss
-Renders differently in
-.Fl T Ns Ar ascii
-mode.
+This section documents compatibility between mandoc and other
+troff implementations, at this time limited to GNU troff
+.Pq Qq groff .
+.Pp
+.Bl -dash -compact
+.It
+The \eN\(aq\(aq escape sequence is limited to printable characters; in
+groff, it accepts arbitrary character numbers.
+.It
+In
+.Fl T Ns Cm ascii ,
+the
+\e(ss, \e(nm, \e(nb, \e(nc, \e(ib, \e(ip, \e(pp, \e[sum], \e[product],
+\e[coproduct], \e(gr, \e(\-h, and \e(a. special characters render
+differently between mandoc and groff.
+.It
+In
+.Fl T Ns Cm html
+and
+.Fl T Ns Cm xhtml ,
+the \e(~=, \e(nb, and \e(nc special characters render differently
+between mandoc and groff.
+.It
+The
+.Fl T Ns Cm ps
+and
+.Fl T Ns Cm pdf
+modes format like
+.Fl T Ns Cm ascii
+instead of rendering glyphs as in groff.
+.It
+The \e[radicalex], \e[sqrtex], and \e(ru special characters have been omitted
+from mandoc either because they are poorly documented or they have no
+known representation.

 .El
 .El

-.\" SECTION

 .Sh SEE ALSO
 .Sh SEE ALSO

-.Xr mandoc 1
-.\" SECTION
+.Xr mandoc 1 ,
+.Xr man 7 ,
+.Xr mdoc 7 ,
+.Xr roff 7

 .Sh AUTHORS
 The
 .Nm
 .Sh AUTHORS
 The
 .Nm

-utility was written by 
-.An Kristaps Dzonsons Aq kristaps@kth.se .
+manual page was written by
+.An Kristaps Dzonsons Aq Mt kristaps@bsd.lv .
+.Sh CAVEATS
+The predefined string
+.Sq \e*(Ba
+mimics the behaviour of the
+.Sq \&|
+character in
+.Xr mdoc 7 ;
+thus, if you wish to render a vertical bar with no side effects, use
+the
+.Sq \e(ba
+escape.