xref: /openbsd-src/share/man/man7/mandoc_char.7 (revision be38755c412cc72cb8d40f51ea70c9893196afff)
1.\"	$OpenBSD: mandoc_char.7,v 1.12 2011/09/18 10:38:57 schwarze Exp $
2.\"
3.\" Copyright (c) 2009 Kristaps Dzonsons <kristaps@bsd.lv>
4.\"
5.\" Permission to use, copy, modify, and distribute this software for any
6.\" purpose with or without fee is hereby granted, provided that the above
7.\" copyright notice and this permission notice appear in all copies.
8.\"
9.\" THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
10.\" WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
11.\" MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
12.\" ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
13.\" WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
14.\" ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
15.\" OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
16.\"
17.Dd $Mdocdate: September 18 2011 $
18.Dt MANDOC_CHAR 7
19.Os
20.Sh NAME
21.Nm mandoc_char
22.Nd mandoc special characters
23.Sh DESCRIPTION
24This page documents the special characters and predefined strings accepted by
25.Xr mandoc 1
26to format
27.Xr mdoc 7
28and
29.Xr man 7
30documents.
31.Pp
32Both
33.Xr mdoc 7
34and
35.Xr man 7
36encode special characters with
37.Sq \eX
38.Pq for a one-character escape ,
39.Sq \e(XX
40.Pq two-character ,
41and
42.Sq \e[N]
43.Pq N-character .
44One may generalise
45.Sq \e(XX
46as
47.Sq \e[XX]
48and
49.Sq \eX
50as
51.Sq \e[X] .
52Predefined strings are functionally similar to special characters, using
53.Sq \e*X
54.Pq for a one-character escape ,
55.Sq \e*(XX
56.Pq two-character ,
57and
58.Sq \e*[N]
59.Pq N-character .
60One may generalise
61.Sq \e*(XX
62as
63.Sq \e*[XX]
64and
65.Sq \e*X
66as
67.Sq \e*[X] .
68.Pp
69Note that each output mode will have a different rendering of the
70characters.
71It's guaranteed that each input symbol will correspond to a
72(more or less) meaningful output rendering, regardless the mode.
73.Sh SPECIAL CHARACTERS
74These are the preferred input symbols for producing special characters.
75.Pp
76Spacing:
77.Bl -column "Input" "Description" -offset indent -compact
78.It Em Input Ta Em Description
79.It \e~      Ta non-breaking, non-collapsing space
80.It \e       Ta breaking, non-collapsing n-width space
81.It \e^      Ta zero-width space
82.It \e%      Ta zero-width space
83.It \e&      Ta zero-width space
84.It \e|      Ta zero-width space
85.It \e0      Ta breaking, non-collapsing digit-width space
86.It \ec      Ta removes any trailing space (if applicable)
87.El
88.Pp
89Lines:
90.Bl -column "Input" "Rendered" "Description" -offset indent -compact
91.It Em Input Ta Em Rendered Ta Em Description
92.It \e(ba    Ta \(ba        Ta bar
93.It \e(br    Ta \(br        Ta box rule
94.It \e(ul    Ta \(ul        Ta underscore
95.It \e(rl    Ta \(rl        Ta overline
96.It \e(bb    Ta \(bb        Ta broken bar
97.It \e(sl    Ta \(sl        Ta forward slash
98.It \e(rs    Ta \(rs        Ta backward slash
99.El
100.Pp
101Text markers:
102.Bl -column "Input" "Rendered" "Description" -offset indent -compact
103.It Em Input Ta Em Rendered Ta Em Description
104.It \e(ci    Ta \(ci        Ta circle
105.It \e(bu    Ta \(bu        Ta bullet
106.It \e(dd    Ta \(dd        Ta double dagger
107.It \e(dg    Ta \(dg        Ta dagger
108.It \e(lz    Ta \(lz        Ta lozenge
109.It \e(sq    Ta \(sq        Ta white square
110.It \e(ps    Ta \(ps        Ta paragraph
111.It \e(sc    Ta \(sc        Ta section
112.It \e(lh    Ta \(lh        Ta left hand
113.It \e(rh    Ta \(rh        Ta right hand
114.It \e(at    Ta \(at        Ta at
115.It \e(sh    Ta \(sh        Ta hash (pound)
116.It \e(CR    Ta \(CR        Ta carriage return
117.It \e(OK    Ta \(OK        Ta check mark
118.El
119.Pp
120Legal symbols:
121.Bl -column "Input" "Rendered" "Description" -offset indent -compact
122.It Em Input Ta Em Rendered Ta Em Description
123.It \e(co    Ta \(co        Ta copyright
124.It \e(rg    Ta \(rg        Ta registered
125.It \e(tm    Ta \(tm        Ta trademarked
126.El
127.Pp
128Punctuation:
129.Bl -column "Input" "Rendered" "Description" -offset indent -compact
130.It Em Input Ta Em Rendered Ta Em Description
131.It \e(em    Ta \(em        Ta em-dash
132.It \e(en    Ta \(en        Ta en-dash
133.It \e(hy    Ta \(hy        Ta hyphen
134.It \ee      Ta \e          Ta back-slash
135.It \e.      Ta \.          Ta period
136.It \e(r!    Ta \(r!        Ta upside-down exclamation
137.It \e(r?    Ta \(r?        Ta upside-down question
138.El
139.Pp
140Quotes:
141.Bl -column "Input" "Rendered" "Description" -offset indent -compact
142.It Em Input Ta Em Rendered Ta Em Description
143.It \e(Bq    Ta \(Bq        Ta right low double-quote
144.It \e(bq    Ta \(bq        Ta right low single-quote
145.It \e(lq    Ta \(lq        Ta left double-quote
146.It \e(rq    Ta \(rq        Ta right double-quote
147.It \e(oq    Ta \(oq        Ta left single-quote
148.It \e(cq    Ta \(cq        Ta right single-quote
149.It \e(aq    Ta \(aq        Ta apostrophe quote (text)
150.It \e(dq    Ta \(dq        Ta double quote (text)
151.It \e(Fo    Ta \(Fo        Ta left guillemet
152.It \e(Fc    Ta \(Fc        Ta right guillemet
153.It \e(fo    Ta \(fo        Ta left single guillemet
154.It \e(fc    Ta \(fc        Ta right single guillemet
155.El
156.Pp
157Brackets:
158.Bl -column "xxbracketrightbpx" Rendered Description -offset indent -compact
159.It Em Input Ta Em Rendered Ta Em Description
160.It \e(lB    Ta \(lB        Ta left bracket
161.It \e(rB    Ta \(rB        Ta right bracket
162.It \e(lC    Ta \(lC        Ta left brace
163.It \e(rC    Ta \(rC        Ta right brace
164.It \e(la    Ta \(la        Ta left angle
165.It \e(ra    Ta \(ra        Ta right angle
166.It \e(bv    Ta \(bv        Ta brace extension
167.It \e[braceex] Ta \[braceex] Ta brace extension
168.It \e[bracketlefttp] Ta \[bracketlefttp] Ta top-left hooked bracket
169.It \e[bracketleftbp] Ta \[bracketleftbp] Ta bottom-left hooked bracket
170.It \e[bracketleftex] Ta \[bracketleftex] Ta left hooked bracket extension
171.It \e[bracketrighttp] Ta \[bracketrighttp] Ta top-right hooked bracket
172.It \e[bracketrightbp] Ta \[bracketrightbp] Ta bottom-right hooked bracket
173.It \e[bracketrightex] Ta \[bracketrightex] Ta right hooked bracket extension
174.It \e(lt    Ta \(lt        Ta top-left hooked brace
175.It \e[bracelefttp] Ta \[bracelefttp] Ta top-left hooked brace
176.It \e(lk    Ta \(lk        Ta mid-left hooked brace
177.It \e[braceleftmid] Ta \[braceleftmid] Ta mid-left hooked brace
178.It \e(lb    Ta \(lb        Ta bottom-left hooked brace
179.It \e[braceleftbp] Ta \[braceleftbp] Ta bottom-left hooked brace
180.It \e[braceleftex] Ta \[braceleftex] Ta left hooked brace extension
181.It \e(rt    Ta \(rt        Ta top-left hooked brace
182.It \e[bracerighttp] Ta \[bracerighttp] Ta top-right hooked brace
183.It \e(rk    Ta \(rk        Ta mid-right hooked brace
184.It \e[bracerightmid] Ta \[bracerightmid] Ta mid-right hooked brace
185.It \e(rb    Ta \(rb        Ta bottom-right hooked brace
186.It \e[bracerightbp] Ta \[bracerightbp] Ta bottom-right hooked brace
187.It \e[bracerightex] Ta \[bracerightex] Ta right hooked brace extension
188.It \e[parenlefttp] Ta \[parenlefttp] Ta top-left hooked parenthesis
189.It \e[parenleftbp] Ta \[parenleftbp] Ta bottom-left hooked parenthesis
190.It \e[parenleftex] Ta \[parenleftex] Ta left hooked parenthesis extension
191.It \e[parenrighttp] Ta \[parenrighttp] Ta top-right hooked parenthesis
192.It \e[parenrightbp] Ta \[parenrightbp] Ta bottom-right hooked parenthesis
193.It \e[parenrightex] Ta \[parenrightex] Ta right hooked parenthesis extension
194.El
195.Pp
196Arrows:
197.Bl -column "Input" "Rendered" "Description" -offset indent -compact
198.It Em Input Ta Em Rendered Ta Em Description
199.It \e(<-    Ta \(<-        Ta left arrow
200.It \e(->    Ta \(->        Ta right arrow
201.It \e(<>    Ta \(<>        Ta left-right arrow
202.It \e(da    Ta \(da        Ta down arrow
203.It \e(ua    Ta \(ua        Ta up arrow
204.It \e(va    Ta \(va        Ta up-down arrow
205.It \e(lA    Ta \(lA        Ta left double-arrow
206.It \e(rA    Ta \(rA        Ta right double-arrow
207.It \e(hA    Ta \(hA        Ta left-right double-arrow
208.It \e(uA    Ta \(uA        Ta up double-arrow
209.It \e(dA    Ta \(dA        Ta down double-arrow
210.It \e(vA    Ta \(vA        Ta up-down double-arrow
211.El
212.Pp
213Logical:
214.Bl -column "Input" "Rendered" "Description" -offset indent -compact
215.It Em Input Ta Em Rendered Ta Em Description
216.It \e(AN    Ta \(AN        Ta logical and
217.It \e(OR    Ta \(OR        Ta logical or
218.It \e(no    Ta \(no        Ta logical not
219.It \e[tno]  Ta \[tno]      Ta logical not (text)
220.It \e(te    Ta \(te        Ta existential quantifier
221.It \e(fa    Ta \(fa        Ta universal quantifier
222.It \e(st    Ta \(st        Ta such that
223.It \e(tf    Ta \(tf        Ta therefore
224.It \e(3d    Ta \(3d        Ta therefore
225.It \e(or    Ta \(or        Ta bitwise or
226.El
227.Pp
228Mathematical:
229.Bl -column "xxcoproductxx" "Rendered" "Description" -offset indent -compact
230.It Em Input Ta Em Rendered Ta Em Description
231.It \e(pl    Ta \(pl        Ta plus
232.It \e(mi    Ta \(mi        Ta minus
233.It \e-      Ta \-          Ta minus (text)
234.It \e(-+    Ta \(-+        Ta minus-plus
235.It \e(+-    Ta \(+-        Ta plus-minus
236.It \e[t+-]  Ta \[t+-]      Ta plus-minus (text)
237.It \e(pc    Ta \(pc        Ta centre-dot
238.It \e(mu    Ta \(mu        Ta multiply
239.It \e[tmu]  Ta \[tmu]      Ta multiply (text)
240.It \e(c*    Ta \(c*        Ta circle-multiply
241.It \e(c+    Ta \(c+        Ta circle-plus
242.It \e(di    Ta \(di        Ta divide
243.It \e[tdi]  Ta \[tdi]      Ta divide (text)
244.It \e(f/    Ta \(f/        Ta fraction
245.It \e(**    Ta \(**        Ta asterisk
246.It \e(<=    Ta \(<=        Ta less-than-equal
247.It \e(>=    Ta \(>=        Ta greater-than-equal
248.It \e(<<    Ta \(<<        Ta much less
249.It \e(>>    Ta \(>>        Ta much greater
250.It \e(eq    Ta \(eq        Ta equal
251.It \e(!=    Ta \(!=        Ta not equal
252.It \e(==    Ta \(==        Ta equivalent
253.It \e(ne    Ta \(ne        Ta not equivalent
254.It \e(=~    Ta \(=~        Ta congruent
255.It \e(-~    Ta \(-~        Ta asymptotically congruent
256.It \e(ap    Ta \(ap        Ta asymptotically similar
257.It \e(~~    Ta \(~~        Ta approximately similar
258.It \e(~=    Ta \(~=        Ta approximately equal
259.It \e(pt    Ta \(pt        Ta proportionate
260.It \e(es    Ta \(es        Ta empty set
261.It \e(mo    Ta \(mo        Ta element
262.It \e(nm    Ta \(nm        Ta not element
263.It \e(sb    Ta \(sb        Ta proper subset
264.It \e(nb    Ta \(nb        Ta not subset
265.It \e(sp    Ta \(sp        Ta proper superset
266.It \e(nc    Ta \(nc        Ta not superset
267.It \e(ib    Ta \(ib        Ta reflexive subset
268.It \e(ip    Ta \(ip        Ta reflexive superset
269.It \e(ca    Ta \(ca        Ta intersection
270.It \e(cu    Ta \(cu        Ta union
271.It \e(/_    Ta \(/_        Ta angle
272.It \e(pp    Ta \(pp        Ta perpendicular
273.It \e(is    Ta \(is        Ta integral
274.It \e[integral] Ta \[integral] Ta integral
275.It \e[sum]    Ta \[sum]   Ta summation
276.It \e[product] Ta \[product] Ta product
277.It \e[coproduct] Ta \[coproduct] Ta coproduct
278.It \e(gr    Ta \(gr        Ta gradient
279.It \e(sr    Ta \(sr        Ta square root
280.It \e[sqrt] Ta \[sqrt]     Ta square root
281.It \e(lc    Ta \(lc        Ta left-ceiling
282.It \e(rc    Ta \(rc        Ta right-ceiling
283.It \e(lf    Ta \(lf        Ta left-floor
284.It \e(rf    Ta \(rf        Ta right-floor
285.It \e(if    Ta \(if        Ta infinity
286.It \e(Ah    Ta \(Ah        Ta aleph
287.It \e(Im    Ta \(Im        Ta imaginary
288.It \e(Re    Ta \(Re        Ta real
289.It \e(pd    Ta \(pd        Ta partial differential
290.It \e(-h    Ta \(-h        Ta Planck constant over 2\(*p
291.It \e[12]   Ta \[12]       Ta one-half
292.It \e[14]   Ta \[14]       Ta one-fourth
293.It \e[34]   Ta \[34]       Ta three-fourths
294.El
295.Pp
296Ligatures:
297.Bl -column "Input" "Rendered" "Description" -offset indent -compact
298.It Em Input Ta Em Rendered Ta Em Description
299.It \e(ff    Ta \(ff        Ta ff ligature
300.It \e(fi    Ta \(fi        Ta fi ligature
301.It \e(fl    Ta \(fl        Ta fl ligature
302.It \e(Fi    Ta \(Fi        Ta ffi ligature
303.It \e(Fl    Ta \(Fl        Ta ffl ligature
304.It \e(AE    Ta \(AE        Ta AE
305.It \e(ae    Ta \(ae        Ta ae
306.It \e(OE    Ta \(OE        Ta OE
307.It \e(oe    Ta \(oe        Ta oe
308.It \e(ss    Ta \(ss        Ta German eszett
309.It \e(IJ    Ta \(IJ        Ta IJ ligature
310.It \e(ij    Ta \(ij        Ta ij ligature
311.El
312.Pp
313Accents:
314.Bl -column "Input" "Rendered" "Description" -offset indent -compact
315.It Em Input Ta Em Rendered Ta Em Description
316.It \e(a"    Ta \(a"        Ta Hungarian umlaut
317.It \e(a-    Ta \(a-        Ta macron
318.It \e(a.    Ta \(a.        Ta dotted
319.It \e(a^    Ta \(a^        Ta circumflex
320.It \e(aa    Ta \(aa        Ta acute
321.It \e'      Ta \'          Ta acute
322.It \e(ga    Ta \(ga        Ta grave
323.It \e`      Ta \`          Ta grave
324.It \e(ab    Ta \(ab        Ta breve
325.It \e(ac    Ta \(ac        Ta cedilla
326.It \e(ad    Ta \(ad        Ta dieresis
327.It \e(ah    Ta \(ah        Ta caron
328.It \e(ao    Ta \(ao        Ta ring
329.It \e(a~    Ta \(a~        Ta tilde
330.It \e(ho    Ta \(ho        Ta ogonek
331.It \e(ha    Ta \(ha        Ta hat (text)
332.It \e(ti    Ta \(ti        Ta tilde (text)
333.El
334.Pp
335Accented letters:
336.Bl -column "Input" "Rendered" "Description" -offset indent -compact
337.It Em Input Ta Em Rendered Ta Em Description
338.It \e('A    Ta \('A        Ta acute A
339.It \e('E    Ta \('E        Ta acute E
340.It \e('I    Ta \('I        Ta acute I
341.It \e('O    Ta \('O        Ta acute O
342.It \e('U    Ta \('U        Ta acute U
343.It \e('a    Ta \('a        Ta acute a
344.It \e('e    Ta \('e        Ta acute e
345.It \e('i    Ta \('i        Ta acute i
346.It \e('o    Ta \('o        Ta acute o
347.It \e('u    Ta \('u        Ta acute u
348.It \e(`A    Ta \(`A        Ta grave A
349.It \e(`E    Ta \(`E        Ta grave E
350.It \e(`I    Ta \(`I        Ta grave I
351.It \e(`O    Ta \(`O        Ta grave O
352.It \e(`U    Ta \(`U        Ta grave U
353.It \e(`a    Ta \(`a        Ta grave a
354.It \e(`e    Ta \(`e        Ta grave e
355.It \e(`i    Ta \(`i        Ta grave i
356.It \e(`o    Ta \(`i        Ta grave o
357.It \e(`u    Ta \(`u        Ta grave u
358.It \e(~A    Ta \(~A        Ta tilde A
359.It \e(~N    Ta \(~N        Ta tilde N
360.It \e(~O    Ta \(~O        Ta tilde O
361.It \e(~a    Ta \(~a        Ta tilde a
362.It \e(~n    Ta \(~n        Ta tilde n
363.It \e(~o    Ta \(~o        Ta tilde o
364.It \e(:A    Ta \(:A        Ta dieresis A
365.It \e(:E    Ta \(:E        Ta dieresis E
366.It \e(:I    Ta \(:I        Ta dieresis I
367.It \e(:O    Ta \(:O        Ta dieresis O
368.It \e(:U    Ta \(:U        Ta dieresis U
369.It \e(:a    Ta \(:a        Ta dieresis a
370.It \e(:e    Ta \(:e        Ta dieresis e
371.It \e(:i    Ta \(:i        Ta dieresis i
372.It \e(:o    Ta \(:o        Ta dieresis o
373.It \e(:u    Ta \(:u        Ta dieresis u
374.It \e(:y    Ta \(:y        Ta dieresis y
375.It \e(^A    Ta \(^A        Ta circumflex A
376.It \e(^E    Ta \(^E        Ta circumflex E
377.It \e(^I    Ta \(^I        Ta circumflex I
378.It \e(^O    Ta \(^O        Ta circumflex O
379.It \e(^U    Ta \(^U        Ta circumflex U
380.It \e(^a    Ta \(^a        Ta circumflex a
381.It \e(^e    Ta \(^e        Ta circumflex e
382.It \e(^i    Ta \(^i        Ta circumflex i
383.It \e(^o    Ta \(^o        Ta circumflex o
384.It \e(^u    Ta \(^u        Ta circumflex u
385.It \e(,C    Ta \(,C        Ta cedilla C
386.It \e(,c    Ta \(,c        Ta cedilla c
387.It \e(/L    Ta \(/L        Ta stroke L
388.It \e(/l    Ta \(/l        Ta stroke l
389.It \e(/O    Ta \(/O        Ta stroke O
390.It \e(/o    Ta \(/o        Ta stroke o
391.It \e(oA    Ta \(oA        Ta ring A
392.It \e(oa    Ta \(oa        Ta ring a
393.El
394.Pp
395Special letters:
396.Bl -column "Input" "Rendered" "Description" -offset indent -compact
397.It Em Input Ta Em Rendered Ta Em Description
398.It \e(-D    Ta \(-D        Ta Eth
399.It \e(Sd    Ta \(Sd        Ta eth
400.It \e(TP    Ta \(TP        Ta Thorn
401.It \e(Tp    Ta \(Tp        Ta thorn
402.It \e(.i    Ta \(.i        Ta dotless i
403.It \e(.j    Ta \(.j        Ta dotless j
404.El
405.Pp
406Currency:
407.Bl -column "Input" "Rendered" "Description" -offset indent -compact
408.It Em Input Ta Em Rendered Ta Em Description
409.It \e(Do    Ta \(Do        Ta dollar
410.It \e(ct    Ta \(ct        Ta cent
411.It \e(Eu    Ta \(Eu        Ta Euro symbol
412.It \e(eu    Ta \(eu        Ta Euro symbol
413.It \e(Ye    Ta \(Ye        Ta yen
414.It \e(Po    Ta \(Po        Ta pound
415.It \e(Cs    Ta \(Cs        Ta Scandinavian
416.It \e(Fn    Ta \(Fn        Ta florin
417.El
418.Pp
419Units:
420.Bl -column "Input" "Rendered" "Description" -offset indent -compact
421.It Em Input Ta Em Rendered Ta Em Description
422.It \e(de    Ta \(de        Ta degree
423.It \e(%0    Ta \(%0        Ta per-thousand
424.It \e(fm    Ta \(fm        Ta minute
425.It \e(sd    Ta \(sd        Ta second
426.It \e(mc    Ta \(mc        Ta micro
427.El
428.Pp
429Greek letters:
430.Bl -column "Input" "Rendered" "Description" -offset indent -compact
431.It Em Input Ta Em Rendered Ta Em Description
432.It \e(*A    Ta \(*A        Ta Alpha
433.It \e(*B    Ta \(*B        Ta Beta
434.It \e(*G    Ta \(*G        Ta Gamma
435.It \e(*D    Ta \(*D        Ta Delta
436.It \e(*E    Ta \(*E        Ta Epsilon
437.It \e(*Z    Ta \(*Z        Ta Zeta
438.It \e(*Y    Ta \(*Y        Ta Eta
439.It \e(*H    Ta \(*H        Ta Theta
440.It \e(*I    Ta \(*I        Ta Iota
441.It \e(*K    Ta \(*K        Ta Kappa
442.It \e(*L    Ta \(*L        Ta Lambda
443.It \e(*M    Ta \(*M        Ta Mu
444.It \e(*N    Ta \(*N        Ta Nu
445.It \e(*C    Ta \(*C        Ta Xi
446.It \e(*O    Ta \(*O        Ta Omicron
447.It \e(*P    Ta \(*P        Ta Pi
448.It \e(*R    Ta \(*R        Ta Rho
449.It \e(*S    Ta \(*S        Ta Sigma
450.It \e(*T    Ta \(*T        Ta Tau
451.It \e(*U    Ta \(*U        Ta Upsilon
452.It \e(*F    Ta \(*F        Ta Phi
453.It \e(*X    Ta \(*X        Ta Chi
454.It \e(*Q    Ta \(*Q        Ta Psi
455.It \e(*W    Ta \(*W        Ta Omega
456.It \e(*a    Ta \(*a        Ta alpha
457.It \e(*b    Ta \(*b        Ta beta
458.It \e(*g    Ta \(*g        Ta gamma
459.It \e(*d    Ta \(*d        Ta delta
460.It \e(*e    Ta \(*e        Ta epsilon
461.It \e(*z    Ta \(*z        Ta zeta
462.It \e(*y    Ta \(*y        Ta eta
463.It \e(*h    Ta \(*h        Ta theta
464.It \e(*i    Ta \(*i        Ta iota
465.It \e(*k    Ta \(*k        Ta kappa
466.It \e(*l    Ta \(*l        Ta lambda
467.It \e(*m    Ta \(*m        Ta mu
468.It \e(*n    Ta \(*n        Ta nu
469.It \e(*c    Ta \(*c        Ta xi
470.It \e(*o    Ta \(*o        Ta omicron
471.It \e(*p    Ta \(*p        Ta pi
472.It \e(*r    Ta \(*r        Ta rho
473.It \e(*s    Ta \(*s        Ta sigma
474.It \e(*t    Ta \(*t        Ta tau
475.It \e(*u    Ta \(*u        Ta upsilon
476.It \e(*f    Ta \(*f        Ta phi
477.It \e(*x    Ta \(*x        Ta chi
478.It \e(*q    Ta \(*q        Ta psi
479.It \e(*w    Ta \(*w        Ta omega
480.It \e(+h    Ta \(+h        Ta theta variant
481.It \e(+f    Ta \(+f        Ta phi variant
482.It \e(+p    Ta \(+p        Ta pi variant
483.It \e(+e    Ta \(+e        Ta epsilon variant
484.It \e(ts    Ta \(ts        Ta sigma terminal
485.El
486.Sh PREDEFINED STRINGS
487Predefined strings are inherited from the macro packages of historical
488troff implementations.
489They are
490.Em not recommended
491for use, as they differ across implementations.
492Manuals using these predefined strings are almost certainly not
493portable.
494.Bl -column "Input" "Rendered" "Description" -offset indent
495.It Em Input Ta Em Rendered Ta Em Description
496.It \e*(Ba   Ta \*(Ba       Ta vertical bar
497.It \e*(Ne   Ta \*(Ne       Ta not equal
498.It \e*(Ge   Ta \*(Ge       Ta greater-than-equal
499.It \e*(Le   Ta \*(Le       Ta less-than-equal
500.It \e*(Gt   Ta \*(Gt       Ta greater-than
501.It \e*(Lt   Ta \*(Lt       Ta less-than
502.It \e*(Pm   Ta \*(Pm       Ta plus-minus
503.It \e*(If   Ta \*(If       Ta infinity
504.It \e*(Pi   Ta \*(Pi       Ta pi
505.It \e*(Na   Ta \*(Na       Ta NaN
506.It \e*(Am   Ta \*(Am       Ta ampersand
507.It \e*R     Ta \*R         Ta restricted mark
508.It \e*(Tm   Ta \*(Tm       Ta trade mark
509.It \e*q     Ta \*q         Ta double-quote
510.It \e*(Rq   Ta \*(Rq       Ta right-double-quote
511.It \e*(Lq   Ta \*(Lq       Ta left-double-quote
512.It \e*(lp   Ta \*(lp       Ta right-parenthesis
513.It \e*(rp   Ta \*(rp       Ta left-parenthesis
514.It \e*(lq   Ta \*(lq       Ta left double-quote
515.It \e*(rq   Ta \*(rq       Ta right double-quote
516.It \e*(ua   Ta \*(ua       Ta up arrow
517.It \e*(va   Ta \*(va       Ta up-down arrow
518.It \e*(<=   Ta \*(<=       Ta less-than-equal
519.It \e*(>=   Ta \*(>=       Ta greater-than-equal
520.It \e*(aa   Ta \*(aa       Ta acute
521.It \e*(ga   Ta \*(ga       Ta grave
522.It \e*(Px   Ta \*(Px       Ta POSIX standard name
523.It \e*(Ai   Ta \*(Ai       Ta ANSI standard name
524.El
525.Sh UNICODE CHARACTERS
526The escape sequence
527.Pp
528.Dl \e[uXXXX]
529.Pp
530is interpreted as a Unicode codepoint.
531The codepoint must be in the range above U+0080 and less than U+10FFFF.
532For compatibility, points must be zero-padded to four characters; if
533greater than four characters, no zero padding is allowed.
534Unicode surrogates are not allowed.
535.Sh NUMBERED CHARACTERS
536For backward compatibility with existing manuals,
537.Xr mandoc 1
538also supports the
539.Pp
540.Dl \eN\(aq Ns Ar number Ns \(aq
541.Pp
542escape sequence, inserting the character
543.Ar number
544from the current character set into the output.
545Of course, this is inherently non-portable and is already marked
546as deprecated in the Heirloom roff manual.
547For example, do not use \eN'34', use \e(dq, or even the plain
548.Sq \(dq
549character where possible.
550.Sh COMPATIBILITY
551This section documents compatibility between mandoc and other other
552troff implementations, at this time limited to GNU troff
553.Pq Qq groff .
554.Pp
555.Bl -dash -compact
556.It
557The \eN\(aq\(aq escape sequence is limited to printable characters; in
558groff, it accepts arbitrary character numbers.
559.It
560In
561.Fl T Ns Cm ascii ,
562the
563\e(ss, \e(nm, \e(nb, \e(nc, \e(ib, \e(ip, \e(pp, \e[sum], \e[product],
564\e[coproduct], \e(gr, \e(\-h, and \e(a. special characters render
565differently between mandoc and groff.
566.It
567In
568.Fl T Ns Cm html
569and
570.Fl T Ns Cm xhtml ,
571the \e(~=, \e(nb, and \e(nc special characters render differently
572between mandoc and groff.
573.It
574The
575.Fl T Ns Cm ps
576and
577.Fl T Ns Cm pdf
578modes format like
579.Fl T Ns Cm ascii
580instead of rendering glyphs as in groff.
581.It
582The \e[radicalex], \e[sqrtex], and \e(ru special characters have been omitted
583from mandoc either because they are poorly documented or they have no
584known representation.
585.El
586.Sh SEE ALSO
587.Xr mandoc 1
588.Sh AUTHORS
589The
590.Nm
591manual page was written by
592.An Kristaps Dzonsons ,
593.Mt kristaps@bsd.lv .
594.Sh CAVEATS
595The
596.Sq \e*(Ba
597escape mimics the behaviour of the
598.Sq \&|
599character in
600.Xr mdoc 7 ;
601thus, if you wish to render a vertical bar with no side effects, use
602the
603.Sq \e(ba
604escape.
605