1ROFF(7) BSD Miscellaneous Information Manual ROFF(7)
2
4 roff — roff language reference for mandoc
5
7 The roff language is a general purpose text formatting language. Since
8 traditional implementations of the mdoc(7) and man(7) manual formatting
9 languages are based on it, many real-world manuals use small numbers of
10 roff requests and escape sequences intermixed with their mdoc(7) or
11 man(7) code. To properly format such manuals, the mandoc(1) utility sup‐
12 ports a subset of roff requests and escapes. Even though this manual
13 page lists all roff requests and escape sequences, it only contains par‐
14 tial information about requests not supported by mandoc(1) and about lan‐
15 guage features that do not matter for manual pages. For complete roff
16 manuals, consult the SEE ALSO section.
17 Input lines beginning with the control character ‘.’ are parsed for
19 requests and macros. Such lines are called “request lines” or “macro
20 lines”, respectively. Requests change the processing state and manipu‐
21 late the formatting; some macros also define the document structure and
22 produce formatted output. The single quote ("'") is accepted as an
23 alternative control character, treated by mandoc(1) just like ‘.’
24 Lines not beginning with control characters are called “text lines”.
26 They provide free-form text to be printed; the formatting of the text
27 depends on the respective processing context.
28
30 roff documents may contain only graphable 7-bit ASCII characters, the
31 space character, and, in certain circumstances, the tab character. The
32 backslash character ‘\’ indicates the start of an escape sequence, used
33 for example for Comments and Special Characters. For a complete listing
34 of escape sequences, consult the ESCAPE SEQUENCE REFERENCE below.
35 Comments
37 Text following an escaped double-quote ‘\"’, whether in a request, macro,
38 or text line, is ignored to the end of the line. A request line begin‐
39 ning with a control character and comment escape ‘.\"’ is also ignored.
40 Furthermore, request lines with only a control character and optional
41 trailing whitespace are stripped from input.
42 Examples:
44 .\" This is a comment line.
45 .\" The next line is ignored:
46 .
47 .Sh EXAMPLES \" This is a comment, too.
48 example text \" And so is this.
49 Special Characters
51 Special characters are used to encode special glyphs and are rendered
52 differently across output media. They may occur in request, macro, and
53 text lines. Sequences begin with the escape character ‘\’ followed by
54 either an open-parenthesis ‘(’ for two-character sequences; an open-
55 bracket ‘[’ for n-character sequences (terminated at a close-bracket
56 ‘]’); or a single one character sequence.
57 Examples:
59 \(em Two-letter em dash escape.
60 \e One-letter backslash escape.
61 See mandoc_char(7) for a complete list.
63 Font Selection
65 In mdoc(7) and man(7) documents, fonts are usually selected with macros.
66 The \f escape sequence and the ft request can be used to manually change
67 the font, but this is not recommended in mdoc(7) documents. Such manual
68 font changes are overridden by many subsequent macros.
69 The following fonts are supported:
71 B Bold font.
73 BI A font that is both bold and italic.
74 CB Bold constant width font. Same as B in terminal output.
75 CI Italic constant width font. Same as I in terminal output.
76 CR Regular constant width font. Same as R in terminal output.
77 CW An alias for CR.
78 I Italic font.
79 P Return to the previous font. If a macro caused a font change
80 since the last \f eascape sequence or ft request, this returns
81 to the font before the last font change in the macro rather
82 than to the font before the last manual font change.
83 R Roman font. This is the default font.
84 1 An alias for R.
85 2 An alias for I.
86 3 An alias for B.
87 4 An alias for BI.
88 Examples:
90 \fBbold\fR
91 Write in bold, then switch to regular font mode.
92 \fIitalic\fP
93 Write in italic, then return to previous font mode.
94 \f(BIbold italic\fP
95 Write in bold italic, then return to previous font mode.
96 Whitespace
98 Whitespace consists of the space character. In text lines, whitespace is
99 preserved within a line. In request and macro lines, whitespace delimits
100 arguments and is discarded.
101 Unescaped trailing spaces are stripped from text line input unless in a
103 literal context. In general, trailing whitespace on any input line is
104 discouraged for reasons of portability. In the rare case that a space
105 character is needed at the end of an input line, it may be forced by
106 ‘\ \&’.
107 Literal space characters can be produced in the output using escape
109 sequences. In macro lines, they can also be included in arguments using
110 quotation; see MACRO SYNTAX for details.
111 Blank text lines, which may include whitespace, are only permitted within
113 literal contexts. If the first character of a text line is a space, that
114 line is printed with a leading newline.
115 Scaling Widths
117 Many requests and macros support scaled widths for their arguments. The
118 syntax for a scaled width is ‘[+-]?[0-9]*.[0-9]*[:unit:]’, where a deci‐
119 mal must be preceded or followed by at least one digit.
120 The following scaling units are accepted:
122 c centimetre
124 i inch
125 P pica (1/6 inch)
126 p point (1/72 inch)
127 f scale ‘u’ by 65536
128 v default vertical span
129 m width of rendered ‘m’ (em) character
130 n width of rendered ‘n’ (en) character
131 u default horizontal span for the terminal
132 M mini-em (1/100 em)
133 Using anything other than ‘m’, ‘n’, or ‘v’ is necessarily non-portable
135 across output media. See COMPATIBILITY.
136 If a scaling unit is not provided, the numerical value is interpreted
138 under the default rules of ‘v’ for vertical spaces and ‘u’ for horizontal
139 ones.
140 Examples:
142 .Bl -tag -width 2i
143 two-inch tagged list indentation in mdoc(7)
144 .HP 2i
145 two-inch tagged list indentation in man(7)
146 .sp 2v
147 two vertical spaces
148 Sentence Spacing
150 Each sentence should terminate at the end of an input line. By doing
151 this, a formatter will be able to apply the proper amount of spacing
152 after the end of sentence (unescaped) period, exclamation mark, or ques‐
153 tion mark followed by zero or more non-sentence closing delimiters (‘)’,
154 ‘]’, ‘'’, ‘"’).
155 The proper spacing is also intelligently preserved if a sentence ends at
157 the boundary of a macro line.
158 Examples:
160 Do not end sentences mid-line like this. Instead,
161 end a sentence like this.
162 A macro would end like this:
163 .Xr mandoc 1 .
164
166 A request or macro line consists of:
167 1. the control character ‘.’ or ‘'’ at the beginning of the line,
169 2. optionally an arbitrary amount of whitespace,
170 3. the name of the request or the macro, which is one word of arbitrary
171 length, terminated by whitespace,
172 4. and zero or more arguments delimited by whitespace.
173 Thus, the following request lines are all equivalent:
175 .ig end
177 .ig end
178 . ig end
179
181 Macros are provided by the mdoc(7) and man(7) languages and can be
182 defined by the de request. When called, they follow the same syntax as
183 requests, except that macro arguments may optionally be quoted by enclos‐
184 ing them in double quote characters (‘"’). Quoted text, even if it con‐
185 tains whitespace or would cause a macro invocation when unquoted, is
186 always considered literal text. Inside quoted text, pairs of double
187 quote characters (‘""’) resolve to single double quote characters.
188 To be recognised as the beginning of a quoted argument, the opening quote
190 character must be preceded by a space character. A quoted argument
191 extends to the next double quote character that is not part of a pair, or
192 to the end of the input line, whichever comes earlier. Leaving out the
193 terminating double quote character at the end of the line is discouraged.
194 For clarity, if more arguments follow on the same input line, it is rec‐
195 ommended to follow the terminating double quote character by a space
196 character; in case the next character after the terminating double quote
197 character is anything else, it is regarded as the beginning of the next,
198 unquoted argument.
199 Both in quoted and unquoted arguments, pairs of backslashes (‘\\’)
201 resolve to single backslashes. In unquoted arguments, space characters
202 can alternatively be included by preceding them with a backslash (‘\ ’),
203 but quoting is usually better for clarity.
204 Examples:
206 .Fn strlen "const char *s"
207 Group arguments "const char *s" into one function argument.
208 If unspecified, "const", "char", and "*s" would be consid‐
209 ered separate arguments.
210 .Op "Fl a"
211 Consider "Fl a" as literal text instead of a flag macro.
212
214 The mandoc(1) roff parser recognises the following requests. For
215 requests marked as "ignored" or "unsupported", any arguments are ignored,
216 and the number of arguments is not checked.
217 ab [message]
219 Abort processing. Currently unsupported.
220 ad [b | c | l | n | r]
222 Set line adjustment mode for subsequent text. Currently ignored.
223 af registername format
225 Assign an output format to a number register. Currently ignored.
226 aln newname oldname
228 Create an alias for a number register. Currently unsupported.
229 als newname oldname
231 Create an alias for a request, string, macro, or diversion.
232 am macroname [endmacro]
234 Append to a macro definition. The syntax of this request is the
235 same as that of de.
236 am1 macroname [endmacro]
238 Append to a macro definition, switching roff compatibility mode
239 off during macro execution (groff extension). The syntax of this
240 request is the same as that of de1. Since mandoc(1) does not
241 implement roff compatibility mode at all, it handles this request
242 as an alias for am.
243 ami macrostring [endstring]
245 Append to a macro definition, specifying the macro name indi‐
246 rectly (groff extension). The syntax of this request is the same
247 as that of dei.
248 ami1 macrostring [endstring]
250 Append to a macro definition, specifying the macro name indi‐
251 rectly and switching roff compatibility mode off during macro
252 execution (groff extension). The syntax of this request is the
253 same as that of dei1. Since mandoc(1) does not implement roff
254 compatibility mode at all, it handles this request as an alias
255 for ami.
256 as stringname [string]
258 Append to a user-defined string. The syntax of this request is
259 the same as that of ds. If a user-defined string with the speci‐
260 fied name does not yet exist, it is set to the empty string
261 before appending.
262 as1 stringname [string]
264 Append to a user-defined string, switching roff compatibility
265 mode off during macro execution (groff extension). The syntax of
266 this request is the same as that of ds1. Since mandoc(1) does
267 not implement roff compatibility mode at all, it handles this
268 request as an alias for as.
269 asciify divname
271 Fully unformat a diversion. Currently unsupported.
272 backtrace
274 Print a backtrace of the input stack. This is a groff extension
275 and currently ignored.
276 bd font [curfont] [offset]
278 Artificially embolden by repeated printing with small shifts.
279 Currently ignored.
280 bleedat left top width height
282 Set the BleedBox page parameter for PDF generation. This is a
283 Heirloom extension and currently ignored.
284 blm macroname
286 Set a blank line trap. Currently unsupported.
287 box divname
289 Begin a diversion without including a partially filled line.
290 Currently unsupported.
291 boxa divname
293 Add to a diversion without including a partially filled line.
294 Currently unsupported.
295 bp [+|-]pagenumber
297 Begin a new page. Currently ignored.
298 BP source height width position offset flags label
300 Define a frame and place a picture in it. This is a Heirloom
301 extension and currently unsupported.
302 br Break the output line.
304 break Break out of a while loop. Currently unsupported.
306 breakchar char ...
308 Optional line break characters. This is a Heirloom extension and
309 currently ignored.
310 brnl N Break output line after the next N input lines. This is a Heir‐
312 loom extension and currently ignored.
313 brp Break and spread output line. Currently, this is implemented as
315 an alias for br.
316 brpnl N
318 Break and spread output line after the next N input lines. This
319 is a Heirloom extension and currently ignored.
320 c2 [char]
322 Change the no-break control character. Currently unsupported.
323 cc [char]
325 Change the control character. If char is not specified, the con‐
326 trol character is reset to ‘.’. Trailing characters are ignored.
327 ce [N] Center the next N input lines without filling. N defaults to 1.
329 An argument of 0 or less ends centering. Currently, high level
330 macros abort centering.
331 cf filename
333 Output the contents of a file. Ignored because insecure.
334 cflags flags char ...
336 Set character flags. This is a groff extension and currently
337 ignored.
338 ch macroname [dist]
340 Change a trap location. Currently ignored.
341 char glyph [string]
343 Define or redefine the ASCII character or character escape
344 sequence glyph to be rendered as string, which can be empty.
345 Only partially supported in mandoc(1); may interact incorrectly
346 with tr.
347 chop stringname
349 Remove the last character from a macro, string, or diversion.
350 Currently unsupported.
351 class classname char ...
353 Define a character class. This is a groff extension and cur‐
354 rently ignored.
355 close streamname
357 Close an open file. Ignored because insecure.
358 CL color text
360 Print text in color. This is a Heirloom extension and currently
361 unsupported.
362 color [1 | 0]
364 Activate or deactivate colors. This is a groff extension and
365 currently ignored.
366 composite from to
368 Define a name component for composite glyph names. This is a
369 groff extension and currently unsupported.
370 continue
372 Immediately start the next iteration of a while loop. Currently
373 unsupported.
374 cp [1 | 0]
376 Switch roff compatibility mode on or off. Currently ignored.
377 cropat left top width height
379 Set the CropBox page parameter for PDF generation. This is a
380 Heirloom extension and currently ignored.
381 cs font [width [emsize]]
383 Constant character spacing mode. Currently ignored.
384 cu [N] Underline next N input lines including whitespace. Currently
386 ignored.
387 da divname
389 Append to a diversion. Currently unsupported.
390 dch macroname [dist]
392 Change a trap location in the current diversion. This is a Heir‐
393 loom extension and currently unsupported.
394 de macroname [endmacro]
396 Define a roff macro. Its syntax can be either
397 .de macroname
399 definition
400 ..
401 or
403 .de macroname endmacro
405 definition
406 .endmacro
407 Both forms define or redefine the macro macroname to represent
409 the definition, which may consist of one or more input lines,
410 including the newline characters terminating each line, option‐
411 ally containing calls to roff requests, roff macros or high-level
412 macros like man(7) or mdoc(7) macros, whichever applies to the
413 document in question.
414 Specifying a custom endmacro works in the same way as for ig;
416 namely, the call to ‘.endmacro’ first ends the definition, and
417 after that, it is also evaluated as a roff request or roff macro,
418 but not as a high-level macro.
419 The macro can be invoked later using the syntax
421 .macroname [argument [argument ...]]
423 Regarding argument parsing, see MACRO SYNTAX above.
425 The line invoking the macro will be replaced in the input stream
427 by the definition, replacing all occurrences of \\$N, where N is
428 a digit, by the Nth argument. For example,
429 .de ZN
431 \fI\^\\$1\^\fP\\$2
432 ..
433 .ZN XtFree .
434 produces
436 \fI\^XtFree\^\fP.
438 in the input stream, and thus in the output: XtFree. Each occur‐
440 rence of \\$* is replaced with all the arguments, joined together
441 with single space characters. The variant \\$@ is similar,
442 except that each argument is individually quoted.
443 Since macros and user-defined strings share a common string ta‐
445 ble, defining a macro macroname clobbers the user-defined string
446 macroname, and the definition can also be printed using the ‘\*’
447 string interpolation syntax described below ds, but this is
448 rarely useful because every macro definition contains at least
449 one explicit newline character.
450 In order to prevent endless recursion, both groff and mandoc(1)
452 limit the stack depth for expanding macros and strings to a
453 large, but finite number, and mandoc(1) also limits the length of
454 the expanded input line. Do not rely on the exact values of
455 these limits.
456 de1 macroname [endmacro]
458 Define a roff macro that will be executed with roff compatibility
459 mode switched off during macro execution. This is a groff exten‐
460 sion. Since mandoc(1) does not implement roff compatibility mode
461 at all, it handles this request as an alias for de.
462 defcolor newname scheme component ...
464 Define a color name. This is a groff extension and currently
465 ignored.
466 dei macrostring [endstring]
468 Define a roff macro, specifying the macro name indirectly (groff
469 extension). The syntax of this request is the same as that of
470 de. The effect is the same as:
471 .de \*[macrostring] [\*[endstring]]
473 dei1 macrostring [endstring]
475 Define a roff macro that will be executed with roff compatibility
476 mode switched off during macro execution, specifying the macro
477 name indirectly (groff extension). Since mandoc(1) does not
478 implement roff compatibility mode at all, it handles this request
479 as an alias for dei.
480 device string ...
482 devicem stringname
484 These two requests only make sense with the groff-specific inter‐
485 mediate output format and are unsupported.
486 di divname
488 Begin a diversion. Currently unsupported.
489 do command [argument ...]
491 Execute roff request or macro line with compatibility mode dis‐
492 abled. Currently unsupported.
493 ds stringname [["]string]
495 Define a user-defined string. The stringname and string argu‐
496 ments are space-separated. If the string begins with a double-
497 quote character, that character will not be part of the string.
498 All remaining characters on the input line form the string,
499 including whitespace and double-quote characters, even trailing
500 ones.
501 The string can be interpolated into subsequent text by using
503 \*[stringname] for a stringname of arbitrary length, or \*(NN or
504 \*N if the length of stringname is two or one characters, respec‐
505 tively. Interpolation can be prevented by escaping the leading
506 backslash; that is, an asterisk preceded by an even number of
507 backslashes does not trigger string interpolation.
508 Since user-defined strings and macros share a common string ta‐
510 ble, defining a string stringname clobbers the macro stringname,
511 and the stringname used for defining a string can also be invoked
512 as a macro, in which case the following input line will be
513 appended to the string, forming a new input line passed to the
514 roff parser. For example,
515 .ds badidea .S
517 .badidea
518 H SYNOPSIS
519 invokes the SH macro when used in a man(7) document. Such abuse
521 is of course strongly discouraged.
522 ds1 stringname [["]string]
524 Define a user-defined string that will be expanded with roff com‐
525 patibility mode switched off during string expansion. This is a
526 groff extension. Since mandoc(1) does not implement roff compat‐
527 ibility mode at all, it handles this request as an alias for ds.
528 dwh dist macroname
530 Set a location trap in the current diversion. This is a Heirloom
531 extension and currently unsupported.
532 dt [dist macroname]
534 Set a trap within a diversion. Currently unsupported.
535 ec [char]
537 Enable the escape mechanism and change the escape character. The
538 char argument defaults to the backslash (‘\’).
539 ecr Restore the escape character. Currently unsupported.
541 ecs Save the escape character. Currently unsupported.
543 el body
545 The “else” half of an if/else conditional. Pops a result off the
546 stack of conditional evaluations pushed by ie and uses it as its
547 conditional. If no stack entries are present (e.g., due to no
548 prior ie calls) then false is assumed. The syntax of this
549 request is similar to if except that the conditional is missing.
550 em macroname
552 Set a trap at the end of input. Currently unsupported.
553 EN End an equation block. See EQ.
555 eo Disable the escape mechanism completely.
557 EP End a picture started by BP. This is a Heirloom extension and
559 currently unsupported.
560 EQ Begin an equation block. See eqn(7) for a description of the
562 equation language.
563 errprint message
565 Print a string like an error message. This is a Heirloom exten‐
566 sion and currently ignored.
567 ev [envname]
569 Switch to another environment. Currently unsupported.
570 evc [envname]
572 Copy an environment into the current environment. Currently
573 unsupported.
574 ex Abort processing and exit. Currently unsupported.
576 fallback curfont font ...
578 Select the fallback sequence for a font. This is a Heirloom
579 extension and currently ignored.
580 fam [familyname]
582 Change the font family. This is a groff extension and currently
583 ignored.
584 fc [delimchar [padchar]]
586 Define a delimiting and a padding character for fields. Cur‐
587 rently unsupported.
588 fchar glyphname [string]
590 Define a fallback glyph. Currently unsupported.
591 fcolor colorname
593 Set the fill color for \D objects. This is a groff extension and
594 currently ignored.
595 fdeferlig font string ...
597 Defer ligature building. This is a Heirloom extension and cur‐
598 rently ignored.
599 feature +|-name
601 Enable or disable an OpenType feature. This is a Heirloom exten‐
602 sion and currently ignored.
603 fi Break the output line and switch to fill mode, which is active by
605 default but can be ended with the nf request. In fill mode,
606 input from subsequent input lines is added to the same output
607 line until the next word no longer fits, at which point the out‐
608 put line is broken. This request is implied by the mdoc(7) Sh
609 macro and by the man(7) SH, SS, and EE macros.
610 fkern font minkern
612 Control the use of kerning tables for a font. This is a Heirloom
613 extension and currently ignored.
614 fl Flush output. Currently ignored.
616 flig font string char ...
618 Define ligatures. This is a Heirloom extension and currently
619 ignored.
620 fp position font [filename]
622 Assign font position. Currently ignored.
623 fps mapname ...
625 Mount a font with a special character map. This is a Heirloom
626 extension and currently ignored.
627 fschar font glyphname [string]
629 Define a font-specific fallback glyph. This is a groff extension
630 and currently unsupported.
631 fspacewidth font [afmunits]
633 Set a font-specific width for the space character. This is a
634 Heirloom extension and currently ignored.
635 fspecial curfont [font ...]
637 Conditionally define a special font. This is a groff extension
638 and currently ignored.
639 ft [font]
641 Change the font; see Font Selection. The font argument defaults
642 to P.
643 ftr newname [oldname]
645 Translate font name. This is a groff extension and currently
646 ignored.
647 fzoom font [permille]
649 Zoom font size. Currently ignored.
650 gcolor [colorname]
652 Set glyph color. This is a groff extension and currently
653 ignored.
654 hc [char]
656 Set the hyphenation character. Currently ignored.
657 hcode char code ...
659 Set hyphenation codes of characters. Currently ignored.
660 hidechar font char ...
662 Hide characters in a font. This is a Heirloom extension and cur‐
663 rently ignored.
664 hla language
666 Set hyphenation language. This is a groff extension and cur‐
667 rently ignored.
668 hlm [number]
670 Set maximum number of consecutive hyphenated lines. Currently
671 ignored.
672 hpf filename
674 Load hyphenation pattern file. This is a groff extension and
675 currently ignored.
676 hpfa filename
678 Load hyphenation pattern file, appending to the current patterns.
679 This is a groff extension and currently ignored.
680 hpfcode code code ...
682 Define mapping values for character codes in hyphenation pat‐
683 terns. This is a groff extension and currently ignored.
684 hw word ...
686 Specify hyphenation points in words. Currently ignored.
687 hy [mode]
689 Set automatic hyphenation mode. Currently ignored.
690 hylang language
692 Set hyphenation language. This is a Heirloom extension and cur‐
693 rently ignored.
694 hylen nchar
696 Minimum word length for hyphenation. This is a Heirloom exten‐
697 sion and currently ignored.
698 hym [length]
700 Set hyphenation margin. This is a groff extension and currently
701 ignored.
702 hypp penalty ...
704 Define hyphenation penalties. This is a Heirloom extension and
705 currently ignored.
706 hys [length]
708 Set hyphenation space. This is a groff extension and currently
709 ignored.
710 ie condition body
712 The “if” half of an if/else conditional. The result of the con‐
713 ditional is pushed into a stack used by subsequent invocations of
714 el, which may be separated by any intervening input (or not exist
715 at all). Its syntax is equivalent to if.
716 if condition body
718 Begin a conditional. This request can also be written as fol‐
719 lows:
720 .if condition \{body
722 body ...\}
723 .if condition \{\
725 body ...
726 .\}
727 The condition is a boolean expression. Currently, mandoc(1) sup‐
729 ports the following subset of roff conditionals:
730 · If ‘!’ is prefixed to condition, it is logically inverted.
732 · If the first character of condition is ‘n’ (nroff mode) or
734 ‘o’ (odd page), it evaluates to true, and the body starts
735 with the next character.
736 · If the first character of condition is ‘e’ (even page), ‘t’
738 (troff mode), or ‘v’ (vroff mode), it evaluates to false, and
739 the body starts with the next character.
740 · If the first character of condition is ‘c’ (character
742 available), it evaluates to true if the following character
743 is an ASCII character or a valid character escape sequence,
744 or to false otherwise. The body starts with the character
745 following that next character.
746 · If the first character of condition is ‘d’, it evaluates to
748 true if the rest of condition is the name of an existing user
749 defined macro or string; otherwise, it evaluates to false.
750 · If the first character of condition is ‘r’, it evaluates to
752 true if the rest of condition is the name of an existing num‐
753 ber register; otherwise, it evaluates to false.
754 · If the condition starts with a parenthesis or with an option‐
756 ally signed integer number, it is evaluated according to the
757 rules of Numerical expressions explained below. It evaluates
758 to true if the result is positive, or to false if the result
759 is zero or negative.
760 · Otherwise, the first character of condition is regarded as a
762 delimiter and it evaluates to true if the string extending
763 from its first to its second occurrence is equal to the
764 string extending from its second to its third occurrence.
765 · If condition cannot be parsed, it evaluates to false.
767 If a conditional is false, its children are not processed, but
769 are syntactically interpreted to preserve the integrity of the
770 input document. Thus,
771 .if t .ig
773 will discard the ‘.ig’, which may lead to interesting results,
775 but
776 .if t .if t \{\
778 will continue to syntactically interpret to the block close of
780 the final conditional. Sub-conditionals, in this case, obviously
781 inherit the truth value of the parent.
782 If the body section is begun by an escaped brace ‘\{’, scope con‐
784 tinues until the end of the input line containing the matching
785 closing-brace escape sequence ‘\}’. If the body is not enclosed
786 in braces, scope continues until the end of the line. If the
787 condition is followed by a body on the same line, whether after a
788 brace or not, then requests and macros must begin with a control
789 character. It is generally more intuitive, in this case, to
790 write
791 .if condition \{\
793 .request
794 .\}
795 than having the request or macro follow as
797 .if condition \{.request
799 The scope of a conditional is always parsed, but only executed if
801 the conditional evaluates to true.
802 Note that the ‘\}’ is converted into a zero-width escape sequence
804 if not passed as a standalone macro ‘.\}’. For example,
805 .Fl a \} b
807 will result in ‘\}’ being considered an argument of the ‘Fl’
809 macro.
810 ig [endmacro]
812 Ignore input. Its syntax can be either
813 .ig
815 ignored text
816 ..
817 or
819 .ig endmacro
821 ignored text
822 .endmacro
823 In the first case, input is ignored until a ‘..’ request is
825 encountered on its own line. In the second case, input is
826 ignored until the specified ‘.endmacro’ is encountered. Do not
827 use the escape character ‘\’ anywhere in the definition of
828 endmacro; it would cause very strange behaviour.
829 When the endmacro is a roff request or a roff macro, like in
831 .ig if
833 the subsequent invocation of if will first terminate the ignored
835 text, then be invoked as usual. Otherwise, it only terminates
836 the ignored text, and arguments following it or the ‘..’ request
837 are discarded.
838 in [[+|-]width]
840 Change indentation. See man(7). Ignored in mdoc(7).
841 index register stringname substring
843 Find a substring in a string. This is a Heirloom extension and
844 currently unsupported.
845 it expression macro
847 Set an input line trap. The named macro will be invoked after
848 processing the number of input text lines specified by the numer‐
849 ical expression. While evaluating the expression, the unit suf‐
850 fixes described below Scaling Widths are ignored.
851 itc expression macro
853 Set an input line trap, not counting lines ending with \c. Cur‐
854 rently unsupported.
855 IX class keystring
857 To support the generation of a table of contents, pod2man(1)
858 emits this user-defined macro, usually without defining it. To
859 avoid reporting large numbers of spurious errors, mandoc(1)
860 ignores it.
861 kern [1 | 0]
863 Switch kerning on or off. Currently ignored.
864 kernafter font char ... afmunits ...
866 Increase kerning after some characters. This is a Heirloom
867 extension and currently ignored.
868 kernbefore font char ... afmunits ...
870 Increase kerning before some characters. This is a Heirloom
871 extension and currently ignored.
872 kernpair font char ... font char ... afmunits
874 Add a kerning pair to the kerning table. This is a Heirloom
875 extension and currently ignored.
876 lc [glyph]
878 Define a leader repetition character. Currently unsupported.
879 lc_ctype localename
881 Set the LC_CTYPE locale. This is a Heirloom extension and cur‐
882 rently unsupported.
883 lds macroname string
885 Define a local string. This is a Heirloom extension and cur‐
886 rently unsupported.
887 length register string
889 Count the number of input characters in a string. Currently
890 unsupported.
891 letadj lspmin lshmin letss lspmax lshmax
893 Dynamic letter spacing and reshaping. This is a Heirloom exten‐
894 sion and currently ignored.
895 lf lineno [filename]
897 Change the line number for error messages. Ignored because inse‐
898 cure.
899 lg [1 | 0]
901 Switch the ligature mechanism on or off. Currently ignored.
902 lhang font char ... afmunits
904 Hang characters at left margin. This is a Heirloom extension and
905 currently ignored.
906 linetabs [1 | 0]
908 Enable or disable line-tabs mode. This is a groff extension and
909 currently unsupported.
910 ll [[+|-]width]
912 Change the output line length. If the width argument is omitted,
913 the line length is reset to its previous value. The default set‐
914 ting for terminal output is 78n. If a sign is given, the line
915 length is added to or subtracted from; otherwise, it is set to
916 the provided value. Using this request in new manuals is dis‐
917 couraged for several reasons, among others because it overrides
918 the mandoc(1) -O width command line option.
919 lnr register [+|-]value [increment]
921 Set local number register. This is a Heirloom extension and cur‐
922 rently unsupported.
923 lnrf register [+|-]value [increment]
925 Set local floating-point register. This is a Heirloom extension
926 and currently unsupported.
927 lpfx string
929 Set a line prefix. This is a Heirloom extension and currently
930 unsupported.
931 ls [factor]
933 Set line spacing. It takes one integer argument specifying the
934 vertical distance of subsequent output text lines measured in v
935 units. Currently ignored.
936 lsm macroname
938 Set a leading spaces trap. This is a groff extension and cur‐
939 rently unsupported.
940 lt [[+|-]width]
942 Set title line length. Currently ignored.
943 mc glyph [dist]
945 Print margin character in the right margin. The dist is cur‐
946 rently ignored; instead, 1n is used.
947 mediasize media
949 Set the device media size. This is a Heirloom extension and cur‐
950 rently ignored.
951 minss width
953 Set minimum word space. This is a Heirloom extension and cur‐
954 rently ignored.
955 mk [register]
957 Mark vertical position. Currently ignored.
958 mso filename
960 Load a macro file using the search path. Ignored because inse‐
961 cure.
962 na Disable adjusting without changing the adjustment mode. Cur‐
964 rently ignored.
965 ne [height]
967 Declare the need for the specified minimum vertical space before
968 the next trap or the bottom of the page. Currently ignored.
969 nf Break the output line and switch to no-fill mode. Subsequent
971 input lines are kept together on the same output line even when
972 exceeding the right margin, and line breaks in subsequent input
973 cause output line breaks. This request is implied by the mdoc(7)
974 Bd -unfilled and Bd -literal macros and by the man(7) EX macro.
975 The fi request switches back to the default fill mode.
976 nh Turn off automatic hyphenation mode. Currently ignored.
978 nhychar char ...
980 Define hyphenation-inhibiting characters. This is a Heirloom
981 extension and currently ignored.
982 nm [start [inc [space [indent]]]]
984 Print line numbers. Currently unsupported.
985 nn [number]
987 Temporarily turn off line numbering. Currently unsupported.
988 nop body
990 Execute the rest of the input line as a request, macro, or text
991 line, skipping the nop request and any space characters immedi‐
992 ately following it. This is mostly used to indent text lines
993 inside macro definitions.
994 nr register [+|-]expression [stepsize]
996 Define or change a register. A register is an arbitrary string
997 value that defines some sort of state, which influences parsing
998 and/or formatting. For the syntax of expression, see Numerical
999 expressions below. If it is prefixed by a sign, the register
1000 will be incremented or decremented instead of assigned to.
1001 The stepsize is used by the \n+ auto-increment feature. It
1003 remains unchanged when omitted while changing an existing regis‐
1004 ter, and it defaults to 0 when defining a new register.
1005 The following register is handled specially:
1007 nS If set to a positive integer value, certain mdoc(7)
1009 macros will behave in the same way as in the SYNOPSIS
1010 section. If set to 0, these macros will behave in the
1011 same way as outside the SYNOPSIS section, even when
1012 called within the SYNOPSIS section itself. Note that
1013 starting a new mdoc(7) section with the Sh macro will
1014 reset this register.
1015 nrf register [+|-]expression [increment]
1017 Define or change a floating-point register. This is a Heirloom
1018 extension and currently unsupported.
1019 nroff Force nroff mode. This is a groff extension and currently
1021 ignored.
1022 ns Turn on no-space mode. Currently ignored.
1024 nx [filename]
1026 Abort processing of the current input file and process another
1027 one. Ignored because insecure.
1028 open stream file
1030 Open a file for writing. Ignored because insecure.
1031 opena stream file
1033 Open a file for appending. Ignored because insecure.
1034 os Output saved vertical space. Currently ignored.
1036 output string
1038 Output directly to intermediate output. Not supported.
1039 padj [1 | 0]
1041 Globally control paragraph-at-once adjustment. This is a Heir‐
1042 loom extension and currently ignored.
1043 papersize media
1045 Set the paper size. This is a Heirloom extension and currently
1046 ignored.
1047 pc [char]
1049 Change the page number character. Currently ignored.
1050 pev Print environments. This is a groff extension and currently
1052 ignored.
1053 pi command
1055 Pipe output to a shell command. Ignored because insecure.
1056 PI Low-level request used by BP. This is a Heirloom extension and
1058 currently unsupported.
1059 pl [[+|-]height]
1061 Change page length. Currently ignored.
1062 pm Print names and sizes of macros, strings, and diversions to stan‐
1064 dard error output. Currently ignored.
1065 pn [+|-]number
1067 Change the page number of the next page. Currently ignored.
1068 pnr Print all number registers on standard error output. Currently
1070 ignored.
1071 po [[+|-]offset]
1073 Set a horizontal page offset. If no argument is specified, the
1074 page offset is reverted to its previous value. If a sign is
1075 specified, the new page offset is calculated relative to the cur‐
1076 rent one; otherwise, it is absolute. The argument follows the
1077 syntax of Scaling Widths and the default scaling unit is m.
1078 ps [[+|-]size]
1080 Change point size. Currently ignored.
1081 psbb filename
1083 Retrieve the bounding box of a PostScript file. Currently unsup‐
1084 ported.
1085 pshape indent length ...
1087 Set a special shape for the current paragraph. This is a Heir‐
1088 loom extension and currently unsupported.
1089 pso command
1091 Include output of a shell command. Ignored because insecure.
1092 ptr Print the names and positions of all traps on standard error out‐
1094 put. This is a groff extension and currently ignored.
1095 pvs [[+|-]height]
1097 Change post-vertical spacing. This is a groff extension and cur‐
1098 rently ignored.
1099 rchar glyph ...
1101 Remove glyph definitions. Currently unsupported.
1102 rd [prompt [argument ...]]
1104 Read from standard input. Currently ignored.
1105 recursionlimit maxrec maxtail
1107 Set the maximum stack depth for recursive macros. This is a
1108 Heirloom extension and currently ignored.
1109 return [twice]
1111 Exit the presently executed macro and return to the caller. The
1112 argument is currently ignored.
1113 rfschar font glyph ...
1115 Remove font-specific fallback glyph definitions. Currently
1116 unsupported.
1117 rhang font char ... afmunits
1119 Hang characters at right margin. This is a Heirloom extension
1120 and currently ignored.
1121 rj [N] Justify the next N input lines to the right margin without fill‐
1123 ing. N defaults to 1. An argument of 0 or less ends right
1124 adjustment.
1125 rm macroname
1127 Remove a request, macro or string.
1128 rn oldname newname
1130 Rename a request, macro, diversion, or string. In mandoc(1),
1131 user-defined macros, mdoc(7) and man(7) macros, and user-defined
1132 strings can be renamed, but renaming of predefined strings and of
1133 roff requests is not supported, and diversions are not imple‐
1134 mented at all.
1135 rnn oldname newname
1137 Rename a number register. Currently unsupported.
1138 rr register
1140 Remove a register.
1141 rs End no-space mode. Currently ignored.
1143 rt [dist]
1145 Return to marked vertical position. Currently ignored.
1146 schar glyph [string]
1148 Define global fallback glyph. This is a groff extension and cur‐
1149 rently unsupported.
1150 sentchar char ...
1152 Define sentence-ending characters. This is a Heirloom extension
1153 and currently ignored.
1154 shc [glyph]
1156 Change the soft hyphen character. Currently ignored.
1157 shift [number]
1159 Shift macro arguments number times, by default once: \\$i becomes
1160 what \\$i+number was. Also decrement \n(.$ by number.
1161 sizes size ...
1163 Define permissible point sizes. This is a groff extension and
1164 currently ignored.
1165 so filename
1167 Include a source file. The file is read and its contents pro‐
1168 cessed as input in place of the so request line. To avoid inad‐
1169 vertent inclusion of unrelated files, mandoc(1) only accepts rel‐
1170 ative paths not containing the strings "../" and "/..".
1171 This request requires man(1) to change to the right directory
1173 before calling mandoc(1), per convention to the root of the man‐
1174 ual tree. Typical usage looks like:
1175 .so man3/Xcursor.3
1177 As the whole concept is rather fragile, the use of so is discour‐
1179 aged. Use ln(1) instead.
1180 sp [height]
1182 Break the output line and emit vertical space. The argument fol‐
1183 lows the syntax of Scaling Widths and defaults to one blank line
1184 (1v).
1185 spacewidth [1 | 0]
1187 Set the space width from the font metrics file. This is a Heir‐
1188 loom extension and currently ignored.
1189 special [font ...]
1191 Define a special font. This is a groff extension and currently
1192 ignored.
1193 spreadwarn [width]
1195 Warn about wide spacing between words. Currently ignored.
1196 ss wordspace [sentencespace]
1198 Set space character size. Currently ignored.
1199 sty position style
1201 Associate style with a font position. This is a groff extension
1202 and currently ignored.
1203 substring stringname startpos [endpos]
1205 Replace a user-defined string with a substring. Currently unsup‐
1206 ported.
1207 sv [height]
1209 Save vertical space. Currently ignored.
1210 sy command
1212 Execute shell command. Ignored because insecure.
1213 T& Re-start a table layout, retaining the options of the prior table
1215 invocation. See TS.
1216 ta [width ... [T width ...]]
1218 Set tab stops. Each width argument follows the syntax of Scaling
1219 Widths. If prefixed by a plus sign, it is relative to the previ‐
1220 ous tab stop. The arguments after the T marker are used repeat‐
1221 edly as often as needed; for each reuse, they are taken relative
1222 to the last previously established tab stop. When ta is called
1223 without arguments, all tab stops are cleared.
1224 tc [glyph]
1226 Change tab repetition character. Currently unsupported.
1227 TE End a table context. See TS.
1229 ti [+|-]width
1231 Break the output line and indent the next output line by width.
1232 If a sign is specified, the temporary indentation is calculated
1233 relative to the current indentation; otherwise, it is absolute.
1234 The argument follows the syntax of Scaling Widths and the default
1235 scaling unit is m.
1236 tkf font minps width1 maxps width2
1238 Enable track kerning for a font. Currently ignored.
1239 tl 'left'center'right'
1241 Print a title line. Currently unsupported.
1242 tm string
1244 Print to standard error output. Currently ignored.
1245 tm1 string
1247 Print to standard error output, allowing leading blanks. This is
1248 a groff extension and currently ignored.
1249 tmc string
1251 Print to standard error output without a trailing newline. This
1252 is a groff extension and currently ignored.
1253 tr glyph glyph ...
1255 Output character translation. The first glyph in each pair is
1256 replaced by the second one. Character escapes can be used; for
1257 example,
1258 tr \(xx\(yy
1260 replaces all invocations of \(xx with \(yy.
1262 track font minps width1 maxps width2
1264 Static letter space tracking. This is a Heirloom extension and
1265 currently ignored.
1266 transchar char ...
1268 Define transparent characters for sentence-ending. This is a
1269 Heirloom extension and currently ignored.
1270 trf filename
1272 Output the contents of a file, disallowing invalid characters.
1273 This is a groff extension and ignored because insecure.
1274 trimat left top width height
1276 Set the TrimBox page parameter for PDF generation. This is a
1277 Heirloom extension and currently ignored.
1278 trin glyph glyph ...
1280 Output character translation, ignored by asciify. Currently
1281 unsupported.
1282 trnt glyph glyph ...
1284 Output character translation, ignored by \!. Currently unsup‐
1285 ported.
1286 troff Force troff mode. This is a groff extension and currently
1288 ignored.
1289 TS Begin a table, which formats input in aligned rows and columns.
1291 See tbl(7) for a description of the tbl language.
1292 uf font
1294 Globally set the underline font. Currently ignored.
1295 ul [N] Underline next N input lines. Currently ignored.
1297 unformat divname
1299 Unformat spaces and tabs in a diversion. Currently unsupported.
1300 unwatch macroname
1302 Disable notification for string or macro. This is a Heirloom
1303 extension and currently ignored.
1304 unwatchn register
1306 Disable notification for register. This is a Heirloom extension
1307 and currently ignored.
1308 vpt [1 | 0]
1310 Enable or disable vertical position traps. This is a groff
1311 extension and currently ignored.
1312 vs [[+|-]height]
1314 Change vertical spacing. Currently ignored.
1315 warn flags
1317 Set warning level. Currently ignored.
1318 warnscale si
1320 Set the scaling indicator used in warnings. This is a groff
1321 extension and currently ignored.
1322 watch macroname
1324 Notify on change of string or macro. This is a Heirloom exten‐
1325 sion and currently ignored.
1326 watchlength maxlength
1328 On change, report the contents of macros and strings up to the
1329 specified length. This is a Heirloom extension and currently
1330 ignored.
1331 watchn register
1333 Notify on change of register. This is a Heirloom extension and
1334 currently ignored.
1335 wh dist [macroname]
1337 Set a page location trap. Currently unsupported.
1338 while condition body
1340 Repeated execution while a condition is true, with syntax similar
1341 to if. Currently implemented with two restrictions: cannot nest,
1342 and each loop must start and end in the same scope.
1343 write ["]string
1345 Write to an open file. Ignored because insecure.
1346 writec ["]string
1348 Write to an open file without appending a newline. Ignored
1349 because insecure.
1350 writem macroname
1352 Write macro or string to an open file. Ignored because insecure.
1353 xflag level
1355 Set the extension level. This is a Heirloom extension and cur‐
1356 rently ignored.
1357 Numerical expressions
1359 The nr, if, and ie requests accept integer numerical expressions as argu‐
1360 ments. These are always evaluated using the C int type; integer overflow
1361 works the same way as in the C language. Numbers consist of an arbitrary
1362 number of digits ‘0’ to ‘9’ prefixed by an optional sign ‘+’ or ‘-’.
1363 Each number may be followed by one optional scaling unit described below
1364 Scaling Widths. The following equations hold:
1365 1i = 6v = 6P = 10m = 10n = 72p = 1000M = 240u = 240
1367 254c = 100i = 24000u = 24000
1368 1f = 65536u = 65536
1369 The following binary operators are implemented. Unless otherwise stated,
1371 they behave as in the C language:
1372 + addition
1374 - subtraction
1375 * multiplication
1376 / division
1377 % remainder of division
1378 < less than
1379 > greater than
1380 == equal to
1381 = equal to, same effect as == (this differs from C)
1382 <= less than or equal to
1383 >= greater than or equal to
1384 <> not equal to (corresponds to C !=; this one is of limited portabil‐
1385 ity, it is supported by Heirloom roff, but not by groff)
1386 & logical and (corresponds to C &&)
1387 : logical or (corresponds to C ||)
1388 <? minimum (not available in C)
1389 >? maximum (not available in C)
1390 There is no concept of precedence; evaluation proceeds from left to
1392 right, except when subexpressions are enclosed in parentheses. Inside
1393 parentheses, whitespace is ignored.
1394
1396 The mandoc(1) roff parser recognises the following escape sequences. In
1397 mdoc(7) and man(7) documents, using escape sequences is discouraged
1398 except for those described in the LANGUAGE SYNTAX section above.
1399 A backslash followed by any character not listed here simply prints that
1401 character itself.
1402 \<newline>
1404 A backslash at the end of an input line can be used to continue
1405 the logical input line on the next physical input line, joining
1406 the text on both lines together as if it were on a single input
1407 line.
1408 \<space>
1410 The escape sequence backslash-space (‘\ ’) is an unpaddable
1411 space-sized non-breaking space character; see Whitespace and
1412 mandoc_char(7).
1413 \! Embed text up to and including the end of the input line into the
1415 current diversion or into intermediate output without interpret‐
1416 ing requests, macros, and escapes. Currently unsupported.
1417 \" The rest of the input line is treated as Comments.
1419 \# Line continuation with comment. Discard the rest of the physical
1421 input line and continue the logical input line on the next physi‐
1422 cal input line, joining the text on both lines together as if it
1423 were on a single input line. This is a groff extension.
1424 \$arg Macro argument expansion, see de.
1426 \% Hyphenation allowed at this point of the word; ignored by
1428 mandoc(1).
1429 \& Non-printing zero-width character, often used for various kinds
1431 of escaping; see Whitespace, mandoc_char(7), and the “MACRO
1432 SYNTAX” and “Delimiters” sections in mdoc(7).
1433 \' Acute accent special character; use \(aa instead.
1435 \(cc Special Characters with two-letter names, see mandoc_char(7).
1437 \) Zero-width space transparent to end-of-sentence detection;
1439 ignored by mandoc(1).
1440 \*[name]
1442 Interpolate the string with the name. For short names, there are
1443 variants \*c and \*(cc.
1444 One string is predefined on the roff language level: \*(.T
1446 expands to the name of the output device, for example ascii,
1447 utf8, ps, pdf, html, or markdown.
1448 Macro sets traditionally predefine additional strings which are
1450 not portable and differ across implementations. Those supported
1451 by mandoc(1) are listed in mandoc_char(7).
1452 Strings can be defined, changed, and deleted with the ds, as, and
1454 rm requests.
1455 \, Left italic correction (groff extension); ignored by mandoc(1).
1457 \- Special character “mathematical minus sign”; see mandoc_char(7)
1459 for details.
1460 \/ Right italic correction (groff extension); ignored by mandoc(1).
1462 \: Breaking the line is allowed at this point of the word without
1464 inserting a hyphen.
1465 \? Embed the text up to the next \? into the current diversion with‐
1467 out interpreting requests, macros, and escapes. This is a groff
1468 extension and currently unsupported.
1469 \[name]
1471 Special Characters with names of arbitrary length, see
1472 mandoc_char(7).
1473 \^ One-twelfth em half-narrow space character, effectively zero-
1475 width in mandoc(1).
1476 \_ Underline special character; use \(ul instead.
1478 \` Grave accent special character; use \(ga instead.
1480 \{ Begin conditional input; see if.
1482 \| One-sixth em narrow space character, effectively zero-width in
1484 mandoc(1).
1485 \} End conditional input; see if.
1487 \~ Paddable non-breaking space character.
1489 \0 Digit width space character.
1491 \A'string'
1493 Anchor definition; ignored by mandoc(1).
1494 \a Leader character; ignored by mandoc(1).
1496 \B'string'
1498 Interpolate ‘1’ if string conforms to the syntax of Numerical
1499 expressions explained above or ‘0’ otherwise.
1500 \b'string'
1502 Bracket building function; ignored by mandoc(1).
1503 \C'name'
1505 Special Characters with names of arbitrary length.
1506 \c When encountered at the end of an input text line, the next input
1508 text line is considered to continue that line, even if there are
1509 request or macro lines in between. No whitespace is inserted.
1510 \D'string'
1512 Draw graphics function; ignored by mandoc(1).
1513 \d Move down by half a line; ignored by mandoc(1).
1515 \E Escape character intended to not be interpreted in copy mode. In
1517 mandoc(1), it currently does the same as \ itself.
1518 \e Backslash special character.
1520 \F[name]
1522 Switch font family (groff extension); ignored by mandoc(1). For
1523 short names, there are variants \Fc and \F(cc.
1524 \f[name]
1526 Switch to the font name, see Font Selection. For short names,
1527 there are variants \fc and \f(cc. An empty name \f[] defaults to
1528 \fP.
1529 \g[name]
1531 Interpolate the format of a number register; ignored by
1532 mandoc(1). For short names, there are variants \gc and \g(cc.
1533 \H'[+|-]number'
1535 Set the height of the current font; ignored by mandoc(1).
1536 \h'[|]width'
1538 Horizontal motion. If the vertical bar is given, the motion is
1539 relative to the current indentation. Otherwise, it is relative
1540 to the current position. The default scaling unit is m.
1541 \k[name]
1543 Mark horizontal input place in register; ignored by mandoc(1).
1544 For short names, there are variants \kc and \k(cc.
1545 \L'number[c]'
1547 Vertical line drawing function; ignored by mandoc(1).
1548 \l'width[c]'
1550 Draw a horizontal line of width using the glyph c.
1551 \M[name]
1553 Set fill (background) color (groff extension); ignored by
1554 mandoc(1). For short names, there are variants \Mc and \M(cc.
1555 \m[name]
1557 Set glyph drawing color (groff extension); ignored by mandoc(1).
1558 For short names, there are variants \mc and \m(cc.
1559 \N'number'
1561 Character number on the current font.
1562 \n[+|-][name]
1564 Interpolate the number register name. For short names, there are
1565 variants \nc and \n(cc. If the optional sign is specified, the
1566 register is first incremented or decremented by the stepsize that
1567 was specified in the relevant nr request, and the changed value
1568 is interpolated.
1569 \Odigit, \O[5arguments]
1571 Suppress output. This is a groff extension and currently unsup‐
1572 ported. With an argument of 1, 2, 3, or 4, it is ignored.
1573 \o'string'
1575 Overstrike, writing all the characters contained in the string to
1576 the same output position. In terminal and HTML output modes,
1577 only the last one of the characters is visible.
1578 \p Break the output line at the end of the current word.
1580 \R'name [+|-]number'
1582 Set number register; ignored by mandoc(1).
1583 \r Move up by one line; ignored by mandoc(1).
1585 \S'number'
1587 Slant output; ignored by mandoc(1).
1588 \s'[+|-]number'
1590 Change point size; ignored by mandoc(1). Alternative forms
1591 \s[+|-]n, \s[+|-]'number', \s[[+|-]number], and \s[+|-][number]
1592 are also parsed and ignored.
1593 \t Horizontal tab; ignored by mandoc(1).
1595 \u Move up by half a line; ignored by mandoc(1).
1597 \V[name]
1599 Interpolate an environment variable; ignored by mandoc(1). For
1600 short names, there are variants \Vc and \V(cc.
1601 \v'number'
1603 Vertical motion; ignored by mandoc(1).
1604 \w'string'
1606 Interpolate the width of the string. The mandoc(1) implementa‐
1607 tion assumes that after expansion of user-defined strings, the
1608 string only contains normal characters, no escape sequences, and
1609 that each character has a width of 24 basic units.
1610 \X'string'
1612 Output string as device control function; ignored in nroff mode
1613 and by mandoc(1).
1614 \x'number'
1616 Extra line space function; ignored by mandoc(1).
1617 \Y[name]
1619 Output a string as a device control function; ignored in nroff
1620 mode and by mandoc(1). For short names, there are variants \Yc
1621 and \Y(cc.
1622 \Z'string'
1624 Print string with zero width and height; ignored by mandoc(1).
1625 \z Output the next character without advancing the cursor position.
1627
1629 The mandoc(1) implementation of the roff language is incomplete. Major
1630 unimplemented features include:
1631 - For security reasons, mandoc(1) never reads or writes external files
1633 except via so requests with safe relative paths.
1634 - There is no automatic hyphenation, no adjustment to the right margin,
1635 and very limited support for centering; the output is always set
1636 flush-left.
1637 - Support for setting tabulator and leader characters is missing, and
1638 support for manually changing indentation is limited.
1639 - The ‘u’ scaling unit is the default terminal unit. In traditional
1640 troff systems, this unit changes depending on the output media.
1641 - Width measurements are implemented in a crude way and often yield
1642 wrong results. Support for explicit movement requests and escapes is
1643 limited.
1644 - There is no concept of output pages, no support for floats, graphics
1645 drawing, and picture inclusion; terminal output is always continuous.
1646 - Requests regarding color, font families, font sizes, and glyph manip‐
1647 ulation are ignored. Font support is very limited. Kerning is not
1648 implemented, and no ligatures are produced.
1649 - The "'" macro control character does not suppress output line breaks.
1650 - Diversions and environments are not implemented, and support for
1651 traps is very incomplete.
1652 - Use of macros is not supported inside tbl(7) code.
1653 The special semantics of the nS number register is an idiosyncracy of
1655 OpenBSD manuals and not supported by other mdoc(7) implementations.
1656
1658 mandoc(1), eqn(7), man(7), mandoc_char(7), mdoc(7), tbl(7)
1659 Joseph F. Ossanna and Brian W. Kernighan, Troff User's Manual, AT&T Bell
1661 Laboratories, Computing Science Technical Report, 54,
1662 http://www.kohala.com/start/troff/cstr54.ps, 1976 and 1992.
1663 Joseph F. Ossanna, Brian W. Kernighan, and Gunnar Ritter, Heirloom
1665 Documentation Tools Nroff/Troff User's Manual,
1666 http://heirloom.sourceforge.net/doctools/troff.pdf, September 17, 2007.
1667
1669 The RUNOFF typesetting system, whose input forms the basis for roff, was
1670 written in MAD and FAP for the CTSS operating system by Jerome E.
1671 Saltzer in 1964. Doug McIlroy rewrote it in BCPL in 1969, renaming it
1672 roff. Dennis M. Ritchie rewrote McIlroy's roff in PDP-11 assembly for
1673 Version 1 AT&T UNIX, Joseph F. Ossanna improved roff and renamed it nroff
1674 for Version 2 AT&T UNIX, then ported nroff to C as troff, which Brian W.
1675 Kernighan released with Version 7 AT&T UNIX. In 1989, James Clarke re-
1676 implemented troff in C++, naming it groff.
1677
1679 This roff reference was written by Kristaps Dzonsons <kristaps@bsd.lv>
1680 and Ingo Schwarze <schwarze@openbsd.org>.
1681BSD May 10, 2020 BSD