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1 .\" $Id: mandoc.1,v 1.146 2015/02/06 03:38:45 schwarze Exp $
2 .\"
3 .\" Copyright (c) 2009, 2010, 2011 Kristaps Dzonsons <kristaps@bsd.lv>
4 .\" Copyright (c) 2012, 2014, 2015 Ingo Schwarze <schwarze@openbsd.org>
5 .\"
6 .\" Permission to use, copy, modify, and distribute this software for any
7 .\" purpose with or without fee is hereby granted, provided that the above
8 .\" copyright notice and this permission notice appear in all copies.
9 .\"
10 .\" THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
11 .\" WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
12 .\" MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
13 .\" ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
14 .\" WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
15 .\" ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
16 .\" OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
17 .\"
18 .Dd $Mdocdate: February 6 2015 $
19 .Dt MANDOC 1
20 .Os
21 .Sh NAME
22 .Nm mandoc
23 .Nd format and display UNIX manuals
24 .Sh SYNOPSIS
25 .Nm mandoc
26 .Op Fl acfhklV
27 .Sm off
28 .Op Fl I Cm os Li = Ar name
29 .Sm on
30 .Op Fl K Ns Ar encoding
31 .Op Fl m Ns Ar format
32 .Op Fl O Ns Ar option
33 .Op Fl T Ns Ar output
34 .Op Fl W Ns Ar level
35 .Op Ar
36 .Sh DESCRIPTION
37 The
38 .Nm
39 utility formats
40 .Ux
41 manual pages for display.
42 .Pp
43 By default,
44 .Nm
45 reads
46 .Xr mdoc 7
47 or
48 .Xr man 7
49 text from stdin, implying
50 .Fl m Ns Cm andoc ,
51 and produces
52 .Fl T Ns Cm locale
53 output.
54 .Pp
55 The options are as follows:
56 .Bl -tag -width Ds
57 .It Fl a
58 If the standard output is a terminal device and
59 .Fl c
60 is not specified, use
61 .Xr more 1
62 to paginate the output, just like
63 .Xr man 1
64 would.
65 .It Fl c
66 Copy the formatted manual pages to the standard output without using
67 .Xr more 1
68 to paginate them.
69 This is the default.
70 It can be specified to override
71 .Fl a .
72 .It Fl f
73 A synonym for
74 .Xr whatis 1 .
75 This overrides any earlier
76 .Fl k
77 and
78 .Fl l
79 options.
80 .Sm off
81 .It Fl I Cm os Li = Ar name
82 .Sm on
83 Override the default operating system
84 .Ar name
85 for the
86 .Xr mdoc 7
87 .Sq \&Os
88 and for the
89 .Xr man 7
90 .Sq \&TH
91 macro.
92 .It Fl h
93 Display only the SYNOPSIS lines.
94 Implies
95 .Fl c .
96 .It Fl K Ns Ar encoding
97 Specify the input encoding.
98 The supported
99 .Ar encoding
100 arguments are
101 .Cm us-ascii ,
102 .Cm iso-8859-1 ,
103 and
104 .Cm utf-8 .
105 If not specified, autodetection uses the first match:
106 .Bl -tag -width iso-8859-1
107 .It Cm utf-8
108 if the first three bytes of the input file
109 are the UTF-8 byte order mark (BOM, 0xefbbbf)
110 .It Ar encoding
111 if the first or second line of the input file matches the
112 .Sy emacs
113 mode line format
114 .Pp
115 .D1 .\e" -*- Oo ...; Oc coding: Ar encoding ; No -*-
116 .It Cm utf-8
117 if the first non-ASCII byte in the file introduces a valid UTF-8 sequence
118 .It Cm iso-8859-1
119 otherwise
120 .El
121 .It Fl k
122 A synonym for
123 .Xr apropos 1 .
124 This overrides any earlier
125 .Fl f
126 and
127 .Fl l
128 options.
129 .It Fl l
130 A synonym for
131 .Fl a .
132 Also reverts any earlier
133 .Fl f
134 and
135 .Fl k
136 options.
137 .It Fl m Ns Ar format
138 Input format.
139 See
140 .Sx Input Formats
141 for available formats.
142 Defaults to
143 .Fl m Ns Cm andoc .
144 .It Fl O Ns Ar option
145 Comma-separated output options.
146 .It Fl T Ns Ar output
147 Output format.
148 See
149 .Sx Output Formats
150 for available formats.
151 Defaults to
152 .Fl T Ns Cm locale .
153 .It Fl V
154 Print version and exit.
155 .It Fl W Ns Ar level
156 Specify the minimum message
157 .Ar level
158 to be reported on the standard error output and to affect the exit status.
159 The
160 .Ar level
161 can be
162 .Cm warning ,
163 .Cm error ,
164 or
165 .Cm unsupp ;
166 .Cm all
167 is an alias for
168 .Cm warning .
169 By default,
170 .Nm
171 is silent.
172 See
173 .Sx EXIT STATUS
174 and
175 .Sx DIAGNOSTICS
176 for details.
177 .Pp
178 The special option
179 .Fl W Ns Cm stop
180 tells
181 .Nm
182 to exit after parsing a file that causes warnings or errors of at least
183 the requested level.
184 No formatted output will be produced from that file.
185 If both a
186 .Ar level
187 and
188 .Cm stop
189 are requested, they can be joined with a comma, for example
190 .Fl W Ns Cm error , Ns Cm stop .
191 .It Ar file
192 Read input from zero or more files.
193 If unspecified, reads from stdin.
194 If multiple files are specified,
195 .Nm
196 will halt with the first failed parse.
197 .El
198 .Pp
199 In
200 .Fl f
201 and
202 .Fl k
203 mode,
204 .Nm
205 also supports the options
206 .Fl CMmOSsw
207 described in the
208 .Xr apropos 1
209 manual.
210 .Ss Input Formats
211 The
212 .Nm
213 utility accepts
214 .Xr mdoc 7
215 and
216 .Xr man 7
217 input with
218 .Fl m Ns Cm doc
219 and
220 .Fl m Ns Cm an ,
221 respectively.
222 The
223 .Xr mdoc 7
224 format is
225 .Em strongly
226 recommended;
227 .Xr man 7
228 should only be used for legacy manuals.
229 .Pp
230 A third option,
231 .Fl m Ns Cm andoc ,
232 which is also the default, determines encoding on-the-fly: if the first
233 non-comment macro is
234 .Sq \&Dd
235 or
236 .Sq \&Dt ,
237 the
238 .Xr mdoc 7
239 parser is used; otherwise, the
240 .Xr man 7
241 parser is used.
242 .Pp
243 If multiple
244 files are specified with
245 .Fl m Ns Cm andoc ,
246 each has its file-type determined this way.
247 If multiple files are
248 specified and
249 .Fl m Ns Cm doc
250 or
251 .Fl m Ns Cm an
252 is specified, then this format is used exclusively.
253 .Ss Output Formats
254 The
255 .Nm
256 utility accepts the following
257 .Fl T
258 arguments, which correspond to output modes:
259 .Bl -tag -width "-Tlocale"
260 .It Fl T Ns Cm ascii
261 Produce 7-bit ASCII output.
262 See
263 .Sx ASCII Output .
264 .It Fl T Ns Cm html
265 Produce HTML5, CSS1, and MathML output.
266 See
267 .Sx HTML Output .
268 .It Fl T Ns Cm lint
269 Parse only: produce no output.
270 Implies
271 .Fl W Ns Cm warning .
272 .It Fl T Ns Cm locale
273 Encode output using the current locale.
274 This is the default.
275 See
276 .Sx Locale Output .
277 .It Fl T Ns Cm man
278 Produce
279 .Xr man 7
280 format output.
281 See
282 .Sx Man Output .
283 .It Fl T Ns Cm pdf
284 Produce PDF output.
285 See
286 .Sx PDF Output .
287 .It Fl T Ns Cm ps
288 Produce PostScript output.
289 See
290 .Sx PostScript Output .
291 .It Fl T Ns Cm tree
292 Produce an indented parse tree.
293 .It Fl T Ns Cm utf8
294 Encode output in the UTF\-8 multi-byte format.
295 See
296 .Sx UTF\-8 Output .
297 .It Fl T Ns Cm xhtml
298 This is a synonym for
299 .Fl T Ns Cm html .
300 .El
301 .Pp
302 If multiple input files are specified, these will be processed by the
303 corresponding filter in-order.
304 .Ss ASCII Output
305 Output produced by
306 .Fl T Ns Cm ascii
307 is rendered in standard 7-bit ASCII documented in
308 .Xr ascii 7 .
309 .Pp
310 Font styles are applied by using back-spaced encoding such that an
311 underlined character
312 .Sq c
313 is rendered as
314 .Sq _ Ns \e[bs] Ns c ,
315 where
316 .Sq \e[bs]
317 is the back-space character number 8.
318 Emboldened characters are rendered as
319 .Sq c Ns \e[bs] Ns c .
320 .Pp
321 The special characters documented in
322 .Xr mandoc_char 7
323 are rendered best-effort in an ASCII equivalent.
324 .Pp
325 Output width is limited to 78 visible columns unless literal input lines
326 exceed this limit.
327 .Pp
328 The following
329 .Fl O
330 arguments are accepted:
331 .Bl -tag -width Ds
332 .It Cm indent Ns = Ns Ar indent
333 The left margin for normal text is set to
334 .Ar indent
335 blank characters instead of the default of five for
336 .Xr mdoc 7
337 and seven for
338 .Xr man 7 .
339 Increasing this is not recommended; it may result in degraded formatting,
340 for example overfull lines or ugly line breaks.
341 .It Cm width Ns = Ns Ar width
342 The output width is set to
343 .Ar width ,
344 which will normalise to \(>=58.
345 .El
346 .Ss HTML Output
347 Output produced by
348 .Fl T Ns Cm html
349 conforms to HTML5 using optional self-closing tags.
350 Default styles use only CSS1.
351 Equations rendered from
352 .Xr eqn 7
353 blocks use MathML.
354 .Pp
355 The
356 .Pa example.style.css
357 file documents style-sheet classes available for customising output.
358 If a style-sheet is not specified with
359 .Fl O Ns Ar style ,
360 .Fl T Ns Cm html
361 defaults to simple output (via an embedded style-sheet)
362 readable in any graphical or text-based web
363 browser.
364 .Pp
365 Special characters are rendered in decimal-encoded UTF\-8.
366 .Pp
367 The following
368 .Fl O
369 arguments are accepted:
370 .Bl -tag -width Ds
371 .It Cm fragment
372 Omit the <!DOCTYPE> declaration and the <html>, <head>, and <body>
373 elements and only emit the subtree below the <body> element.
374 The
375 .Cm style
376 argument will be ignored.
377 This is useful when embedding manual content within existing documents.
378 .It Cm includes Ns = Ns Ar fmt
379 The string
380 .Ar fmt ,
381 for example,
382 .Ar ../src/%I.html ,
383 is used as a template for linked header files (usually via the
384 .Sq \&In
385 macro).
386 Instances of
387 .Sq \&%I
388 are replaced with the include filename.
389 The default is not to present a
390 hyperlink.
391 .It Cm man Ns = Ns Ar fmt
392 The string
393 .Ar fmt ,
394 for example,
395 .Ar ../html%S/%N.%S.html ,
396 is used as a template for linked manuals (usually via the
397 .Sq \&Xr
398 macro).
399 Instances of
400 .Sq \&%N
401 and
402 .Sq %S
403 are replaced with the linked manual's name and section, respectively.
404 If no section is included, section 1 is assumed.
405 The default is not to
406 present a hyperlink.
407 .It Cm style Ns = Ns Ar style.css
408 The file
409 .Ar style.css
410 is used for an external style-sheet.
411 This must be a valid absolute or
412 relative URI.
413 .El
414 .Ss Locale Output
415 Locale-depending output encoding is triggered with
416 .Fl T Ns Cm locale .
417 This is the default.
418 .Pp
419 This option is not available on all systems: systems without locale
420 support, or those whose internal representation is not natively UCS-4,
421 will fall back to
422 .Fl T Ns Cm ascii .
423 See
424 .Sx ASCII Output
425 for font style specification and available command-line arguments.
426 .Ss Man Output
427 Translate input format into
428 .Xr man 7
429 output format.
430 This is useful for distributing manual sources to legacy systems
431 lacking
432 .Xr mdoc 7
433 formatters.
434 .Pp
435 If
436 .Xr mdoc 7
437 is passed as input, it is translated into
438 .Xr man 7 .
439 If the input format is
440 .Xr man 7 ,
441 the input is copied to the output, expanding any
442 .Xr roff 7
443 .Sq so
444 requests.
445 The parser is also run, and as usual, the
446 .Fl W
447 level controls which
448 .Sx DIAGNOSTICS
449 are displayed before copying the input to the output.
450 .Ss PDF Output
451 PDF-1.1 output may be generated by
452 .Fl T Ns Cm pdf .
453 See
454 .Sx PostScript Output
455 for
456 .Fl O
457 arguments and defaults.
458 .Ss PostScript Output
459 PostScript
460 .Qq Adobe-3.0
461 Level-2 pages may be generated by
462 .Fl T Ns Cm ps .
463 Output pages default to letter sized and are rendered in the Times font
464 family, 11-point.
465 Margins are calculated as 1/9 the page length and width.
466 Line-height is 1.4m.
467 .Pp
468 Special characters are rendered as in
469 .Sx ASCII Output .
470 .Pp
471 The following
472 .Fl O
473 arguments are accepted:
474 .Bl -tag -width Ds
475 .It Cm paper Ns = Ns Ar name
476 The paper size
477 .Ar name
478 may be one of
479 .Ar a3 ,
480 .Ar a4 ,
481 .Ar a5 ,
482 .Ar legal ,
483 or
484 .Ar letter .
485 You may also manually specify dimensions as
486 .Ar NNxNN ,
487 width by height in millimetres.
488 If an unknown value is encountered,
489 .Ar letter
490 is used.
491 .El
492 .Ss UTF\-8 Output
493 Use
494 .Fl T Ns Cm utf8
495 to force a UTF\-8 locale.
496 See
497 .Sx Locale Output
498 for details and options.
499 .Sh ENVIRONMENT
500 .Bl -tag -width MANPAGER
501 .It Ev MANPAGER
502 Any non-empty value of the environment variable
503 .Ev MANPAGER
504 will be used instead of the standard pagination program,
505 .Xr more 1 .
506 .It Ev PAGER
507 Specifies the pagination program to use when
508 .Ev MANPAGER
509 is not defined.
510 If neither PAGER nor MANPAGER is defined,
511 .Pa /usr/bin/more Fl s
512 will be used.
513 .El
514 .Sh EXIT STATUS
515 The
516 .Nm
517 utility exits with one of the following values, controlled by the message
518 .Ar level
519 associated with the
520 .Fl W
521 option:
522 .Pp
523 .Bl -tag -width Ds -compact
524 .It 0
525 No warnings or errors occurred, or those that did were ignored because
526 they were lower than the requested
527 .Ar level .
528 .It 2
529 At least one warning occurred, but no error, and
530 .Fl W Ns Cm warning
531 was specified.
532 .It 3
533 At least one parsing error occurred,
534 but no unsupported feature was encountered, and
535 .Fl W Ns Cm error
536 or
537 .Fl W Ns Cm warning
538 was specified.
539 .It 4
540 At least one unsupported feature was encountered, and
541 .Fl W Ns Cm unsupp ,
542 .Fl W Ns Cm error
543 or
544 .Fl W Ns Cm warning
545 was specified.
546 .It 5
547 Invalid command line arguments were specified.
548 No input files have been read.
549 .It 6
550 An operating system error occurred, for example exhaustion
551 of memory, file descriptors, or process table entries.
552 Such errors cause
553 .Nm
554 to exit at once, possibly in the middle of parsing or formatting a file.
555 .El
556 .Pp
557 Note that selecting
558 .Fl T Ns Cm lint
559 output mode implies
560 .Fl W Ns Cm warning .
561 .Sh EXAMPLES
562 To page manuals to the terminal:
563 .Pp
564 .Dl $ mandoc \-Wall,stop mandoc.1 2\*(Gt&1 | less
565 .Dl $ mandoc mandoc.1 mdoc.3 mdoc.7 | less
566 .Pp
567 To produce HTML manuals with
568 .Ar style.css
569 as the style-sheet:
570 .Pp
571 .Dl $ mandoc \-Thtml -Ostyle=style.css mdoc.7 \*(Gt mdoc.7.html
572 .Pp
573 To check over a large set of manuals:
574 .Pp
575 .Dl $ mandoc \-Tlint `find /usr/src -name \e*\e.[1-9]`
576 .Pp
577 To produce a series of PostScript manuals for A4 paper:
578 .Pp
579 .Dl $ mandoc \-Tps \-Opaper=a4 mdoc.7 man.7 \*(Gt manuals.ps
580 .Pp
581 Convert a modern
582 .Xr mdoc 7
583 manual to the older
584 .Xr man 7
585 format, for use on systems lacking an
586 .Xr mdoc 7
587 parser:
588 .Pp
589 .Dl $ mandoc \-Tman foo.mdoc \*(Gt foo.man
590 .Sh DIAGNOSTICS
591 Messages displayed by
592 .Nm
593 follow this format:
594 .Pp
595 .D1 Nm Ns : Ar file : Ns Ar line : Ns Ar column : level : message : macro args
596 .Pp
597 Line and column numbers start at 1.
598 Both are omitted for messages referring to an input file as a whole.
599 Macro names and arguments are omitted where meaningless.
600 Fatal messages about invalid command line arguments
601 or operating system errors, for example when memory is exhausted,
602 may also omit the
603 .Ar file
604 and
605 .Ar level
606 fields.
607 .Pp
608 Message levels have the following meanings:
609 .Bl -tag -width "warning"
610 .It Cm unsupp
611 An input file uses unsupported low-level
612 .Xr roff 7
613 features.
614 The output may be incomplete and/or misformatted,
615 so using GNU troff instead of
616 .Nm
617 to process the file may be preferable.
618 .It Cm error
619 An input file contains invalid syntax that cannot be safely interpreted.
620 By discarding part of the input or inserting missing tokens,
621 the parser is able to continue, and the error does not prevent
622 generation of formatted output, but typically, preparing that
623 output involves information loss, broken document structure
624 or unintended formatting, no matter whether
625 .Nm
626 or GNU troff is used.
627 In many cases, the output of
628 .Nm
629 and GNU troff is identical, but in some,
630 .Nm
631 is more resilient than GNU troff with respect to malformed input.
632 .Pp
633 Non-existent or unreadable input files are also reported on the
634 .Cm error
635 level.
636 In that case, the parser cannot even be started and no output
637 is produced from those input files.
638 .It Cm warning
639 An input file uses obsolete, discouraged or non-portable syntax.
640 All the same, the meaning of the input is unambiguous and a correct
641 rendering can be produced.
642 Documents causing warnings may render poorly when using other
643 formatting tools instead of
644 .Nm .
645 .El
646 .Pp
647 Messages of the
648 .Cm warning ,
649 .Cm error ,
650 and
651 .Cm unsupp
652 levels except those about non-existent or unreadable input files
653 are hidden unless their level, or a lower level, is requested using a
654 .Fl W
655 option or
656 .Fl T Ns Cm lint
657 output mode.
658 .Ss Warnings related to the document prologue
659 .Bl -ohang
660 .It Sy "missing manual title, using UNTITLED"
661 .Pq mdoc
662 A
663 .Ic \&Dt
664 macro has no arguments, or there is no
665 .Ic \&Dt
666 macro before the first non-prologue macro.
667 .It Sy "missing manual title, using \(dq\(dq"
668 .Pq man
669 There is no
670 .Ic \&TH
671 macro, or it has no arguments.
672 .It Sy "lower case character in document title"
673 .Pq mdoc , man
674 The title is still used as given in the
675 .Ic \&Dt
676 or
677 .Ic \&TH
678 macro.
679 .It Sy "missing manual section, using \(dq\(dq"
680 .Pq mdoc , man
681 A
682 .Ic \&Dt
683 or
684 .Ic \&TH
685 macro lacks the mandatory section argument.
686 .It Sy "unknown manual section"
687 .Pq mdoc
688 The section number in a
689 .Ic \&Dt
690 line is invalid, but still used.
691 .It Sy "missing date, using today's date"
692 .Pq mdoc, man
693 The document was parsed as
694 .Xr mdoc 7
695 and it has no
696 .Ic \&Dd
697 macro, or the
698 .Ic \&Dd
699 macro has no arguments or only empty arguments;
700 or the document was parsed as
701 .Xr man 7
702 and it has no
703 .Ic \&TH
704 macro, or the
705 .Ic \&TH
706 macro has less than three arguments or its third argument is empty.
707 .It Sy "cannot parse date, using it verbatim"
708 .Pq mdoc , man
709 The date given in a
710 .Ic \&Dd
711 or
712 .Ic \&TH
713 macro does not follow the conventional format.
714 .It Sy "missing Os macro, using \(dq\(dq"
715 .Pq mdoc
716 The default or current system is not shown in this case.
717 .It Sy "duplicate prologue macro"
718 .Pq mdoc
719 One of the prologue macros occurs more than once.
720 The last instance overrides all previous ones.
721 .It Sy "late prologue macro"
722 .Pq mdoc
723 A
724 .Ic \&Dd
725 or
726 .Ic \&Os
727 macro occurs after some non-prologue macro, but still takes effect.
728 .It Sy "skipping late title macro"
729 .Pq mdoc
730 The
731 .Ic \&Dt
732 macro can only occur before the first non-prologue macro
733 because traditional formatters write the page header
734 before parsing the document body.
735 Even though this technical restriction does not apply to
736 .Nm ,
737 traditional semantics is preserved.
738 The late macro is discarded including its arguments.
739 .It Sy "prologue macros out of order"
740 .Pq mdoc
741 The prologue macros are not given in the conventional order
742 .Ic \&Dd ,
743 .Ic \&Dt ,
744 .Ic \&Os .
745 All three macros are used even when given in another order.
746 .El
747 .Ss Warnings regarding document structure
748 .Bl -ohang
749 .It Sy ".so is fragile, better use ln(1)"
750 .Pq roff
751 Including files only works when the parser program runs with the correct
752 current working directory.
753 .It Sy "no document body"
754 .Pq mdoc , man
755 The document body contains neither text nor macros.
756 An empty document is shown, consisting only of a header and a footer line.
757 .It Sy "content before first section header"
758 .Pq mdoc , man
759 Some macros or text precede the first
760 .Ic \&Sh
761 or
762 .Ic \&SH
763 section header.
764 The offending macros and text are parsed and added to the top level
765 of the syntax tree, outside any section block.
766 .It Sy "first section is not NAME"
767 .Pq mdoc
768 The argument of the first
769 .Ic \&Sh
770 macro is not
771 .Sq NAME .
772 This may confuse
773 .Xr makewhatis 8
774 and
775 .Xr apropos 1 .
776 .It Sy "bad NAME section contents"
777 .Pq mdoc
778 The last node in the NAME section is not an
779 .Ic \&Nd
780 macro, or any preceding macro is not
781 .Ic \&Nm ,
782 or the NAME section is completely empty.
783 This may confuse
784 .Xr makewhatis 8
785 and
786 .Xr apropos 1 .
787 .It Sy "missing description line, using \(dq\(dq"
788 .Pq mdoc
789 The
790 .Ic \&Nd
791 macro lacks the required argument.
792 The title line of the manual will end after the dash.
793 .It Sy "sections out of conventional order"
794 .Pq mdoc
795 A standard section occurs after another section it usually precedes.
796 All section titles are used as given,
797 and the order of sections is not changed.
798 .It Sy "duplicate section title"
799 .Pq mdoc
800 The same standard section title occurs more than once.
801 .It Sy "unexpected section"
802 .Pq mdoc
803 A standard section header occurs in a section of the manual
804 where it normally isn't useful.
805 .It Sy "unusual Xr order"
806 .Pq mdoc
807 In the SEE ALSO section, an
808 .Ic \&Xr
809 macro with a lower section number follows one with a higher number,
810 or two
811 .Ic \&Xr
812 macros refering to the same section are out of alphabetical order.
813 .It Sy "unusual Xr punctuation"
814 .Pq mdoc
815 In the SEE ALSO section, punctuation between two
816 .Ic \&Xr
817 macros differs from a single comma, or there is trailing punctuation
818 after the last
819 .Ic \&Xr
820 macro.
821 .It Sy "AUTHORS section without An macro"
822 .Pq mdoc
823 An AUTHORS sections contains no
824 .Ic \&An
825 macros, or only empty ones.
826 Probably, there are author names lacking markup.
827 .El
828 .Ss "Warnings related to macros and nesting"
829 .Bl -ohang
830 .It Sy "obsolete macro"
831 .Pq mdoc
832 See the
833 .Xr mdoc 7
834 manual for replacements.
835 .It Sy "macro neither callable nor escaped"
836 .Pq mdoc
837 The name of a macro that is not callable appears on a macro line.
838 It is printed verbatim.
839 If the intention is to call it, move it to its own line;
840 otherwise, escape it by prepending
841 .Sq \e& .
842 .It Sy "skipping paragraph macro"
843 In
844 .Xr mdoc 7
845 documents, this happens
846 .Bl -dash -compact
847 .It
848 at the beginning and end of sections and subsections
849 .It
850 right before non-compact lists and displays
851 .It
852 at the end of items in non-column, non-compact lists
853 .It
854 and for multiple consecutive paragraph macros.
855 .El
856 In
857 .Xr man 7
858 documents, it happens
859 .Bl -dash -compact
860 .It
861 for empty
862 .Ic \&P ,
863 .Ic \&PP ,
864 and
865 .Ic \&LP
866 macros
867 .It
868 for
869 .Ic \&IP
870 macros having neither head nor body arguments
871 .It
872 for
873 .Ic \&br
874 or
875 .Ic \&sp
876 right after
877 .Ic \&SH
878 or
879 .Ic \&SS
880 .El
881 .It Sy "moving paragraph macro out of list"
882 .Pq mdoc
883 A list item in a
884 .Ic \&Bl
885 list contains a trailing paragraph macro.
886 The paragraph macro is moved after the end of the list.
887 .It Sy "skipping no-space macro"
888 .Pq mdoc
889 An input line begins with an
890 .Ic \&Ns
891 macro.
892 The macro is ignored.
893 .It Sy "blocks badly nested"
894 .Pq mdoc
895 If two blocks intersect, one should completely contain the other.
896 Otherwise, rendered output is likely to look strange in any output
897 format, and rendering in SGML-based output formats is likely to be
898 outright wrong because such languages do not support badly nested
899 blocks at all.
900 Typical examples of badly nested blocks are
901 .Qq Ic \&Ao \&Bo \&Ac \&Bc
902 and
903 .Qq Ic \&Ao \&Bq \&Ac .
904 In these examples,
905 .Ic \&Ac
906 breaks
907 .Ic \&Bo
908 and
909 .Ic \&Bq ,
910 respectively.
911 .It Sy "nested displays are not portable"
912 .Pq mdoc
913 A
914 .Ic \&Bd ,
915 .Ic \&D1 ,
916 or
917 .Ic \&Dl
918 display occurs nested inside another
919 .Ic \&Bd
920 display.
921 This works with
922 .Nm ,
923 but fails with most other implementations.
924 .It Sy "moving content out of list"
925 .Pq mdoc
926 A
927 .Ic \&Bl
928 list block contains text or macros before the first
929 .Ic \&It
930 macro.
931 The offending children are moved before the beginning of the list.
932 .It Sy ".Vt block has child macro"
933 .Pq mdoc
934 The
935 .Ic \&Vt
936 macro supports plain text arguments only.
937 Formatting may be ugly and semantic searching
938 for the affected content might not work.
939 .It Sy "fill mode already enabled, skipping"
940 .Pq man
941 A
942 .Ic \&fi
943 request occurs even though the document is still in fill mode,
944 or already switched back to fill mode.
945 It has no effect.
946 .It Sy "fill mode already disabled, skipping"
947 .Pq man
948 An
949 .Ic \&nf
950 request occurs even though the document already switched to no-fill mode
951 and did not switch back to fill mode yet.
952 It has no effect.
953 .It Sy "line scope broken"
954 .Pq man
955 While parsing the next-line scope of the previous macro,
956 another macro is found that prematurely terminates the previous one.
957 The previous, interrupted macro is deleted from the parse tree.
958 .El
959 .Ss "Warnings related to missing arguments"
960 .Bl -ohang
961 .It Sy "skipping empty request"
962 .Pq roff , eqn
963 The macro name is missing from a macro definition request,
964 or an
965 .Xr eqn 7
966 control statement or operation keyword lacks its required argument.
967 .It Sy "conditional request controls empty scope"
968 .Pq roff
969 A conditional request is only useful if any of the following
970 follows it on the same logical input line:
971 .Bl -dash -compact
972 .It
973 The
974 .Sq \e{
975 keyword to open a multi-line scope.
976 .It
977 A request or macro or some text, resulting in a single-line scope.
978 .It
979 The immediate end of the logical line without any intervening whitespace,
980 resulting in next-line scope.
981 .El
982 Here, a conditional request is followed by trailing whitespace only,
983 and there is no other content on its logical input line.
984 Note that it doesn't matter whether the logical input line is split
985 across multiple physical input lines using
986 .Sq \e
987 line continuation characters.
988 This is one of the rare cases
989 where trailing whitespace is syntactically significant.
990 The conditional request controls a scope containing whitespace only,
991 so it is unlikely to have a significant effect,
992 except that it may control a following
993 .Ic \&el
994 clause.
995 .It Sy "skipping empty macro"
996 .Pq mdoc
997 The indicated macro has no arguments or no body content
998 and hence no effect.
999 .It Sy "empty argument, using 0n"
1000 .Pq mdoc
1001 The required width is missing after
1002 .Ic \&Bd
1003 or
1004 .Ic \&Bl
1005 .Fl offset
1006 or
1007 .Fl width.
1008 .It Sy "argument count wrong"
1009 .Pq mdoc , man
1010 The indicated macro has too few or too many arguments.
1011 The syntax tree will contain the wrong number of arguments as given.
1012 Formatting behaviour depends on the specific macro in question.
1013 Note that the same message may also occur as an ERROR, see below.
1014 .It Sy "missing display type, using -ragged"
1015 .Pq mdoc
1016 The
1017 .Ic \&Bd
1018 macro is invoked without the required display type.
1019 .It Sy "list type is not the first argument"
1020 .Pq mdoc
1021 In a
1022 .Ic \&Bl
1023 macro, at least one other argument precedes the type argument.
1024 The
1025 .Nm
1026 utility copes with any argument order, but some other
1027 .Xr mdoc 7
1028 implementations do not.
1029 .It Sy "missing -width in -tag list, using 8n"
1030 .Pq mdoc
1031 Every
1032 .Ic \&Bl
1033 macro having the
1034 .Fl tag
1035 argument requires
1036 .Fl width ,
1037 too.
1038 .It Sy "missing utility name, using \(dq\(dq"
1039 .Pq mdoc
1040 The
1041 .Ic \&Ex Fl std
1042 macro is called without an argument before
1043 .Ic \&Nm
1044 has first been called with an argument.
1045 .It Sy "missing function name, using \(dq\(dq"
1046 .Pq mdoc
1047 The
1048 .Ic \&Fo
1049 macro is called without an argument.
1050 No function name is printed.
1051 .It Sy "empty head in list item"
1052 .Pq mdoc
1053 In a
1054 .Ic \&Bl
1055 .Fl diag ,
1056 .Fl hang ,
1057 .Fl inset ,
1058 .Fl ohang ,
1059 or
1060 .Fl tag
1061 list, an
1062 .Ic \&It
1063 macro lacks the required argument.
1064 The item head is left empty.
1065 .It Sy "empty list item"
1066 .Pq mdoc
1067 In a
1068 .Ic \&Bl
1069 .Fl bullet ,
1070 .Fl dash ,
1071 .Fl enum ,
1072 or
1073 .Fl hyphen
1074 list, an
1075 .Ic \&It
1076 block is empty.
1077 An empty list item is shown.
1078 .It Sy "missing font type"
1079 .Pq mdoc
1080 A
1081 .Ic \&Bf
1082 macro has no argument.
1083 It switches to the default font,
1084 .Cm \efR .
1085 .It Sy "unknown font type"
1086 .Pq mdoc
1087 The
1088 .Ic \&Bf
1089 argument is invalid.
1090 The default font
1091 .Cm \efR
1092 is used instead.
1093 .It Sy "nothing follows prefix"
1094 .Pq mdoc
1095 A
1096 .Ic \&Pf
1097 macro has no argument, or only one argument and no macro follows
1098 on the same input line.
1099 This defeats its purpose; in particular, spacing is not suppressed
1100 before the text or macros following on the next input line.
1101 .It Sy "empty reference block"
1102 .Pq mdoc
1103 An
1104 .Ic \&Rs
1105 macro is immediately followed by an
1106 .Ic \&Re
1107 macro on the next input line.
1108 Such an empty block does not produce any output.
1109 .It Sy "missing -std argument, adding it"
1110 .Pq mdoc
1111 An
1112 .Ic \&Ex
1113 or
1114 .Ic \&Rv
1115 macro lacks the required
1116 .Fl std
1117 argument.
1118 The
1119 .Nm
1120 utility assumes
1121 .Fl std
1122 even when it is not specified, but other implementations may not.
1123 .It Sy "missing eqn box, using \(dq\(dq"
1124 .Pq eqn
1125 A diacritic mark or a binary operator is found,
1126 but there is nothing to the left of it.
1127 An empty box is inserted.
1128 .El
1129 .Ss "Warnings related to bad macro arguments"
1130 .Bl -ohang
1131 .It Sy "unterminated quoted argument"
1132 .Pq roff
1133 Macro arguments can be enclosed in double quote characters
1134 such that space characters and macro names contained in the quoted
1135 argument need not be escaped.
1136 The closing quote of the last argument of a macro can be omitted.
1137 However, omitting it is not recommended because it makes the code
1138 harder to read.
1139 .It Sy "duplicate argument"
1140 .Pq mdoc
1141 A
1142 .Ic \&Bd
1143 or
1144 .Ic \&Bl
1145 macro has more than one
1146 .Fl compact ,
1147 more than one
1148 .Fl offset ,
1149 or more than one
1150 .Fl width
1151 argument.
1152 All but the last instances of these arguments are ignored.
1153 .It Sy "skipping duplicate argument"
1154 .Pq mdoc
1155 An
1156 .Ic \&An
1157 macro has more than one
1158 .Fl split
1159 or
1160 .Fl nosplit
1161 argument.
1162 All but the first of these arguments are ignored.
1163 .It Sy "skipping duplicate display type"
1164 .Pq mdoc
1165 A
1166 .Ic \&Bd
1167 macro has more than one type argument; the first one is used.
1168 .It Sy "skipping duplicate list type"
1169 .Pq mdoc
1170 A
1171 .Ic \&Bl
1172 macro has more than one type argument; the first one is used.
1173 .It Sy "skipping -width argument"
1174 .Pq mdoc
1175 A
1176 .Ic \&Bl
1177 .Fl column ,
1178 .Fl diag ,
1179 .Fl ohang ,
1180 .Fl inset ,
1181 or
1182 .Fl item
1183 list has a
1184 .Fl width
1185 argument.
1186 That has no effect.
1187 .It Sy "unknown AT&T UNIX version"
1188 .Pq mdoc
1189 An
1190 .Ic \&At
1191 macro has an invalid argument.
1192 It is used verbatim, with
1193 .Qq "AT&T UNIX "
1194 prefixed to it.
1195 .It Sy "comma in function argument"
1196 .Pq mdoc
1197 An argument of an
1198 .Ic \&Fa
1199 or
1200 .Ic \&Fn
1201 macro contains a comma; it should probably be split into two arguments.
1202 .It Sy "parenthesis in function name"
1203 .Pq mdoc
1204 The first argument of an
1205 .Ic \&Fc
1206 or
1207 .Ic \&Fn
1208 macro contains an opening or closing parenthesis; that's probably wrong,
1209 parentheses are added automatically.
1210 .It Sy "invalid content in Rs block"
1211 .Pq mdoc
1212 An
1213 .Ic \&Rs
1214 block contains plain text or non-% macros.
1215 The bogus content is left in the syntax tree.
1216 Formatting may be poor.
1217 .It Sy "invalid Boolean argument"
1218 .Pq mdoc
1219 An
1220 .Ic \&Sm
1221 macro has an argument other than
1222 .Cm on
1223 or
1224 .Cm off .
1225 The invalid argument is moved out of the macro, which leaves the macro
1226 empty, causing it to toggle the spacing mode.
1227 .It Sy "unknown font, skipping request"
1228 .Pq man , tbl
1229 A
1230 .Xr roff 7
1231 .Ic \&ft
1232 request or a
1233 .Xr tbl 7
1234 .Ic \&f
1235 layout modifier has an unknown
1236 .Ar font
1237 argument.
1238 .El
1239 .Ss "Warnings related to plain text"
1240 .Bl -ohang
1241 .It Sy "blank line in fill mode, using .sp"
1242 .Pq mdoc
1243 The meaning of blank input lines is only well-defined in non-fill mode:
1244 In fill mode, line breaks of text input lines are not supposed to be
1245 significant.
1246 However, for compatibility with groff, blank lines in fill mode
1247 are replaced with
1248 .Ic \&sp
1249 requests.
1250 .It Sy "tab in filled text"
1251 .Pq mdoc , man
1252 The meaning of tab characters is only well-defined in non-fill mode:
1253 In fill mode, whitespace is not supposed to be significant
1254 on text input lines.
1255 As an implementation dependent choice, tab characters on text lines
1256 are passed through to the formatters in any case.
1257 Given that the text before the tab character will be filled,
1258 it is hard to predict which tab stop position the tab will advance to.
1259 .It Sy "whitespace at end of input line"
1260 .Pq mdoc , man , roff
1261 Whitespace at the end of input lines is almost never semantically
1262 significant \(em but in the odd case where it might be, it is
1263 extremely confusing when reviewing and maintaining documents.
1264 .It Sy "bad comment style"
1265 .Pq roff
1266 Comment lines start with a dot, a backslash, and a double-quote character.
1267 The
1268 .Nm
1269 utility treats the line as a comment line even without the backslash,
1270 but leaving out the backslash might not be portable.
1271 .It Sy "invalid escape sequence"
1272 .Pq roff
1273 An escape sequence has an invalid opening argument delimiter, lacks the
1274 closing argument delimiter, or the argument has too few characters.
1275 If the argument is incomplete,
1276 .Ic \e*
1277 and
1278 .Ic \en
1279 expand to an empty string,
1280 .Ic \eB
1281 to the digit
1282 .Sq 0 ,
1283 and
1284 .Ic \ew
1285 to the length of the incomplete argument.
1286 All other invalid escape sequences are ignored.
1287 .It Sy "undefined string, using \(dq\(dq"
1288 .Pq roff
1289 If a string is used without being defined before,
1290 its value is implicitly set to the empty string.
1291 However, defining strings explicitly before use
1292 keeps the code more readable.
1293 .El
1294 .Ss "Warnings related to tables"
1295 .Bl -ohang
1296 .It Sy "tbl line starts with span"
1297 .Pq tbl
1298 The first cell in a table layout line is a horizontal span
1299 .Pq Sq Cm s .
1300 Data provided for this cell is ignored, and nothing is printed in the cell.
1301 .It Sy "tbl column starts with span"
1302 .Pq tbl
1303 The first line of a table layout specification
1304 requests a vertical span
1305 .Pq Sq Cm ^ .
1306 Data provided for this cell is ignored, and nothing is printed in the cell.
1307 .It Sy "skipping vertical bar in tbl layout"
1308 .Pq tbl
1309 A table layout specification contains more than two consecutive vertical bars.
1310 A double bar is printed, all additional bars are discarded.
1311 .El
1312 .Ss "Errors related to tables"
1313 .Bl -ohang
1314 .It Sy "non-alphabetic character in tbl options"
1315 .Pq tbl
1316 The table options line contains a character other than a letter,
1317 blank, or comma where the beginning of an option name is expected.
1318 The character is ignored.
1319 .It Sy "skipping unknown tbl option"
1320 .Pq tbl
1321 The table options line contains a string of letters that does not
1322 match any known option name.
1323 The word is ignored.
1324 .It Sy "missing tbl option argument"
1325 .Pq tbl
1326 A table option that requires an argument is not followed by an
1327 opening parenthesis, or the opening parenthesis is immediately
1328 followed by a closing parenthesis.
1329 The option is ignored.
1330 .It Sy "wrong tbl option argument size"
1331 .Pq tbl
1332 A table option argument contains an invalid number of characters.
1333 Both the option and the argument are ignored.
1334 .It Sy "empty tbl layout"
1335 .Pq tbl
1336 A table layout specification is completely empty,
1337 specifying zero lines and zero columns.
1338 As a fallback, a single left-justified column is used.
1339 .It Sy "invalid character in tbl layout"
1340 .Pq tbl
1341 A table layout specification contains a character that can neither
1342 be interpreted as a layout key character nor as a layout modifier,
1343 or a modifier precedes the first key.
1344 The invalid character is discarded.
1345 .It Sy "unmatched parenthesis in tbl layout"
1346 .Pq tbl
1347 A table layout specification contains an opening parenthesis,
1348 but no matching closing parenthesis.
1349 The rest of the input line, starting from the parenthesis, has no effect.
1350 .It Sy "tbl without any data cells"
1351 .Pq tbl
1352 A table does not contain any data cells.
1353 It will probably produce no output.
1354 .It Sy "ignoring data in spanned tbl cell"
1355 .Pq tbl
1356 A table cell is marked as a horizontal span
1357 .Pq Sq Cm s
1358 or vertical span
1359 .Pq Sq Cm ^
1360 in the table layout, but it contains data.
1361 The data is ignored.
1362 .It Sy "ignoring extra tbl data cells"
1363 .Pq tbl
1364 A data line contains more cells than the corresponding layout line.
1365 The data in the extra cells is ignored.
1366 .It Sy "data block open at end of tbl"
1367 .Pq tbl
1368 A data block is opened with
1369 .Cm T{ ,
1370 but never closed with a matching
1371 .Cm T} .
1372 The remaining data lines of the table are all put into one cell,
1373 and any remaining cells stay empty.
1374 .El
1375 .Ss "Errors related to roff, mdoc, and man code"
1376 .Bl -ohang
1377 .It Sy "input stack limit exceeded, infinite loop?"
1378 .Pq roff
1379 Explicit recursion limits are implemented for the following features,
1380 in order to prevent infinite loops:
1381 .Bl -dash -compact
1382 .It
1383 expansion of nested escape sequences
1384 including expansion of strings and number registers,
1385 .It
1386 expansion of nested user-defined macros,
1387 .It
1388 and
1389 .Ic \&so
1390 file inclusion.
1391 .El
1392 When a limit is hit, the output is incorrect, typically losing
1393 some content, but the parser can continue.
1394 .It Sy "skipping bad character"
1395 .Pq mdoc , man , roff
1396 The input file contains a byte that is not a printable
1397 .Xr ascii 7
1398 character.
1399 The message mentions the character number.
1400 The offending byte is replaced with a question mark
1401 .Pq Sq \&? .
1402 Consider editing the input file to replace the byte with an ASCII
1403 transliteration of the intended character.
1404 .It Sy "skipping unknown macro"
1405 .Pq mdoc , man , roff
1406 The first identifier on a request or macro line is neither recognized as a
1407 .Xr roff 7
1408 request, nor as a user-defined macro, nor, respectively, as an
1409 .Xr mdoc 7
1410 or
1411 .Xr man 7
1412 macro.
1413 It may be mistyped or unsupported.
1414 The request or macro is discarded including its arguments.
1415 .It Sy "skipping insecure request"
1416 .Pq roff
1417 An input file attempted to run a shell command
1418 or to read or write an external file.
1419 Such attempts are denied for security reasons.
1420 .It Sy "skipping item outside list"
1421 .Pq mdoc , eqn
1422 An
1423 .Ic \&It
1424 macro occurs outside any
1425 .Ic \&Bl
1426 list, or an
1427 .Xr eqn 7
1428 .Ic above
1429 delimiter occurs outside any pile.
1430 It is discarded including its arguments.
1431 .It Sy "skipping column outside column list"
1432 .Pq mdoc
1433 A
1434 .Ic \&Ta
1435 macro occurs outside any
1436 .Ic \&Bl Fl column
1437 block.
1438 It is discarded including its arguments.
1439 .It Sy "skipping end of block that is not open"
1440 .Pq mdoc , man , eqn , tbl , roff
1441 Various syntax elements can only be used to explicitly close blocks
1442 that have previously been opened.
1443 An
1444 .Xr mdoc 7
1445 block closing macro, a
1446 .Xr man 7
1447 .Ic \&RE
1448 or
1449 .Ic \&UE
1450 macro, an
1451 .Xr eqn 7
1452 right delimiter or closing brace, or the end of an equation, table, or
1453 .Xr roff 7
1454 conditional request is encountered but no matching block is open.
1455 The offending request or macro is discarded.
1456 .It Sy "fewer RS blocks open, skipping"
1457 .Pq man
1458 The
1459 .Ic \&RE
1460 macro is invoked with an argument, but less than the specified number of
1461 .Ic \&RS
1462 blocks is open.
1463 The
1464 .Ic \&RE
1465 macro is discarded.
1466 .It Sy "inserting missing end of block"
1467 .Pq mdoc , tbl
1468 Various
1469 .Xr mdoc 7
1470 macros as well as tables require explicit closing by dedicated macros.
1471 A block that doesn't support bad nesting
1472 ends before all of its children are properly closed.
1473 The open child nodes are closed implicitly.
1474 .It Sy "scope open on exit"
1475 .Pq mdoc , man , eqn , tbl , roff
1476 At the end of the document, an explicit
1477 .Xr mdoc 7
1478 block, a
1479 .Xr man 7
1480 next-line scope or
1481 .Ic \&RS
1482 or
1483 .Ic \&UR
1484 block, an equation, table, or
1485 .Xr roff 7
1486 conditional or ignore block is still open.
1487 The open block is closed implicitly.
1488 .It Sy "escaped character not allowed in a name"
1489 .Pq roff
1490 Macro, string and register identifiers consist of printable,
1491 non-whitespace ASCII characters.
1492 Escape sequences and characters and strings expressed in terms of them
1493 cannot form part of a name.
1494 The first argument of an
1495 .Ic \&am ,
1496 .Ic \&as ,
1497 .Ic \&de ,
1498 .Ic \&ds ,
1499 .Ic \&nr ,
1500 or
1501 .Ic \&rr
1502 request, or any argument of an
1503 .Ic \&rm
1504 request, or the name of a request or user defined macro being called,
1505 is terminated by an escape sequence.
1506 In the cases of
1507 .Ic \&as ,
1508 .Ic \&ds ,
1509 and
1510 .Ic \&nr ,
1511 the request has no effect at all.
1512 In the cases of
1513 .Ic \&am ,
1514 .Ic \&de ,
1515 .Ic \&rr ,
1516 and
1517 .Ic \&rm ,
1518 what was parsed up to this point is used as the arguments to the request,
1519 and the rest of the input line is discarded including the escape sequence.
1520 When parsing for a request or a user-defined macro name to be called,
1521 only the escape sequence is discarded.
1522 The characters preceding it are used as the request or macro name,
1523 the characters following it are used as the arguments to the request or macro.
1524 .It Sy "argument count wrong"
1525 .Pq mdoc , man , roff
1526 The indicated request or macro has too few or too many arguments.
1527 The syntax tree will contain the wrong number of arguments as given.
1528 Formatting behaviour depends on the specific request or macro in question.
1529 Note that the same message may also occur as a WARNING, see above.
1530 .It Sy "NOT IMPLEMENTED: Bd -file"
1531 .Pq mdoc
1532 For security reasons, the
1533 .Ic \&Bd
1534 macro does not support the
1535 .Fl file
1536 argument.
1537 By requesting the inclusion of a sensitive file, a malicious document
1538 might otherwise trick a privileged user into inadvertently displaying
1539 the file on the screen, revealing the file content to bystanders.
1540 The argument is ignored including the file name following it.
1541 .It Sy "missing list type, using -item"
1542 .Pq mdoc
1543 A
1544 .Ic \&Bl
1545 macro fails to specify the list type.
1546 .It Sy "missing manual name, using \(dq\(dq"
1547 .Pq mdoc
1548 The first call to
1549 .Ic \&Nm
1550 lacks the required argument.
1551 .It Sy "uname(3) system call failed, using UNKNOWN"
1552 .Pq mdoc
1553 The
1554 .Ic \&Os
1555 macro is called without arguments, and the
1556 .Xr uname 3
1557 system call failed.
1558 As a workaround,
1559 .Nm
1560 can be compiled with
1561 .Sm off
1562 .Fl D Cm OSNAME=\(dq\e\(dq Ar string Cm \e\(dq\(dq .
1563 .Sm on
1564 .It Sy "unknown standard specifier"
1565 .Pq mdoc
1566 An
1567 .Ic \&St
1568 macro has an unknown argument and is discarded.
1569 .It Sy "skipping request without numeric argument"
1570 .Pq roff , eqn
1571 An
1572 .Ic \&it
1573 request or an
1574 .Xr eqn 7
1575 .Ic \&size
1576 or
1577 .Ic \&gsize
1578 statement has a non-numeric or negative argument or no argument at all.
1579 The invalid request or statement is ignored.
1580 .It Sy "NOT IMPLEMENTED: .so with absolute path or \(dq..\(dq"
1581 .Pq roff
1582 For security reasons,
1583 .Nm
1584 allows
1585 .Ic \&so
1586 file inclusion requests only with relative paths
1587 and only without ascending to any parent directory.
1588 By requesting the inclusion of a sensitive file, a malicious document
1589 might otherwise trick a privileged user into inadvertently displaying
1590 the file on the screen, revealing the file content to bystanders.
1591 .Nm
1592 only shows the path as it appears behind
1593 .Ic \&so .
1594 .It Sy ".so request failed"
1595 .Pq roff
1596 Servicing a
1597 .Ic \&so
1598 request requires reading an external file, but the file could not be
1599 opened.
1600 .Nm
1601 only shows the path as it appears behind
1602 .Ic \&so .
1603 .It Sy "skipping all arguments"
1604 .Pq mdoc , man , eqn , roff
1605 An
1606 .Xr mdoc 7
1607 .Ic \&Bt ,
1608 .Ic \&Ed ,
1609 .Ic \&Ef ,
1610 .Ic \&Ek ,
1611 .Ic \&El ,
1612 .Ic \&Lp ,
1613 .Ic \&Pp ,
1614 .Ic \&Re ,
1615 .Ic \&Rs ,
1616 or
1617 .Ic \&Ud
1618 macro, an
1619 .Ic \&It
1620 macro in a list that don't support item heads, a
1621 .Xr man 7
1622 .Ic \&LP ,
1623 .Ic \&P ,
1624 or
1625 .Ic \&PP
1626 macro, an
1627 .Xr eqn 7
1628 .Ic \&EQ
1629 or
1630 .Ic \&EN
1631 macro, or a
1632 .Xr roff 7
1633 .Ic \&br
1634 request or
1635 .Sq \&..
1636 block closing request is invoked with at least one argument.
1637 All arguments are ignored.
1638 .It Sy "skipping excess arguments"
1639 .Pq mdoc , man , roff
1640 The
1641 .Ic \&An
1642 macro is invoked with another argument after
1643 .Fl split
1644 or
1645 .Fl nosplit ,
1646 .Ic \&Fo
1647 is invoked with more than one argument,
1648 .Ic \&Bd ,
1649 .Ic \&Bk ,
1650 or
1651 .Ic \&Bl
1652 are invoked with invalid arguments, the
1653 .Ic \&RE
1654 macro is invoked with more than one argument
1655 or with a non-integer argument, the
1656 .Ic \&sp
1657 request is invoked with more than one argument, or a request of the
1658 .Ic \&de
1659 family is invoked with more than two arguments.
1660 The excess arguments are ignored.
1661 .El
1662 .Ss Unsupported features
1663 .Bl -ohang
1664 .It Sy "input too large"
1665 .Pq mdoc , man
1666 Currently,
1667 .Nm
1668 cannot handle input files larger than its arbitrary size limit
1669 of 2^31 bytes (2 Gigabytes).
1670 Since useful manuals are always small, this is not a problem in practice.
1671 Parsing is aborted as soon as the condition is detected.
1672 .It Sy "unsupported control character"
1673 .Pq roff
1674 An ASCII control character supported by other
1675 .Xr roff 7
1676 implementations but not by
1677 .Nm
1678 was found in an input file.
1679 It is replaced by a question mark.
1680 .It Sy "unsupported roff request"
1681 .Pq roff
1682 An input file contains a
1683 .Xr roff 7
1684 request supported by GNU troff or Heirloom troff but not by
1685 .Nm ,
1686 and it is likely that this will cause information loss
1687 or considerable misformatting.
1688 .It Sy "eqn delim option in tbl"
1689 .Pq eqn , tbl
1690 The options line of a table defines equation delimiters.
1691 Any equation source code contained in the table will be printed unformatted.
1692 .It Sy "unsupported table layout modifier"
1693 .Pq tbl
1694 A table layout specification contains an
1695 .Sq Cm m
1696 modifier.
1697 The modifier is discarded.
1698 .It Sy "ignoring macro in table"
1699 .Pq tbl , mdoc , man
1700 A table contains an invocation of an
1701 .Xr mdoc 7
1702 or
1703 .Xr man 7
1704 macro or of an undefined macro.
1705 The macro is ignored, and its arguments are handled
1706 as if they were a text line.
1707 .El
1708 .Sh SEE ALSO
1709 .Xr apropos 1 ,
1710 .Xr man 1 ,
1711 .Xr eqn 7 ,
1712 .Xr man 7 ,
1713 .Xr mandoc_char 7 ,
1714 .Xr mdoc 7 ,
1715 .Xr roff 7 ,
1716 .Xr tbl 7
1717 .Sh AUTHORS
1718 The
1719 .Nm
1720 utility was written by
1721 .An Kristaps Dzonsons Aq Mt kristaps@bsd.lv
1722 and is maintained by
1723 .An Ingo Schwarze Aq Mt schwarze@openbsd.org .
1724 .Sh BUGS
1725 In
1726 .Fl T Ns Cm html ,
1727 the maximum size of an element attribute is determined by
1728 .Dv BUFSIZ ,
1729 which is usually 1024 bytes.
1730 Be aware of this when setting long link
1731 formats such as
1732 .Fl O Ns Cm style Ns = Ns Ar really/long/link .