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1 .\" $Id: mandoc.1,v 1.176 2017/03/04 17:17:34 schwarze Exp $
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3 .\" Copyright (c) 2009, 2010, 2011 Kristaps Dzonsons <kristaps@bsd.lv>
4 .\" Copyright (c) 2012, 2014-2017 Ingo Schwarze <schwarze@openbsd.org>
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6 .\" Permission to use, copy, modify, and distribute this software for any
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10 .\" THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
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18 .Dd $Mdocdate: March 4 2017 $
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 acfhkl
27 .Op Fl I Cm os Ns = Ns Ar name
28 .Op Fl K Ar encoding
29 .Op Fl m Ns Ar format
30 .Op Fl O Ar option
31 .Op Fl T Ar output
32 .Op Fl W Ar level
33 .Op Ar
34 .Sh DESCRIPTION
35 The
36 .Nm
37 utility formats
38 .Ux
39 manual pages for display.
40 .Pp
41 By default,
42 .Nm
43 reads
44 .Xr mdoc 7
45 or
46 .Xr man 7
47 text from stdin, implying
48 .Fl m Ns Cm andoc ,
49 and produces
50 .Fl T Cm locale
51 output.
52 .Pp
53 The options are as follows:
54 .Bl -tag -width Ds
55 .It Fl a
56 If the standard output is a terminal device and
57 .Fl c
58 is not specified, use
59 .Xr more 1
60 to paginate the output, just like
61 .Xr man 1
62 would.
63 .It Fl c
64 Copy the formatted manual pages to the standard output without using
65 .Xr more 1
66 to paginate them.
67 This is the default.
68 It can be specified to override
69 .Fl a .
70 .It Fl f
71 A synonym for
72 .Xr whatis 1 .
73 This overrides any earlier
74 .Fl k
75 and
76 .Fl l
77 options.
78 .It Fl h
79 Display only the SYNOPSIS lines.
80 Implies
81 .Fl c .
82 .It Fl I Cm os Ns = Ns Ar name
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 K Ar encoding
93 Specify the input encoding.
94 The supported
95 .Ar encoding
96 arguments are
97 .Cm us-ascii ,
98 .Cm iso-8859-1 ,
99 and
100 .Cm utf-8 .
101 If not specified, autodetection uses the first match in the following
102 list:
103 .Bl -enum
104 .It
105 If the first three bytes of the input file are the UTF-8 byte order
106 mark (BOM, 0xefbbbf), input is interpreted as
107 .Cm utf-8 .
108 .It
109 If the first or second line of the input file matches the
110 .Sy emacs
111 mode line format
112 .Pp
113 .D1 .\e" -*- Oo ...; Oc coding: Ar encoding ; No -*-
114 .Pp
115 then input is interpreted according to
116 .Ar encoding .
117 .It
118 If the first non-ASCII byte in the file introduces a valid UTF-8
119 sequence, input is interpreted as
120 .Cm utf-8 .
121 .It
122 Otherwise, input is interpreted as
123 .Cm iso-8859-1 .
124 .El
125 .It Fl k
126 A synonym for
127 .Xr apropos 1 .
128 This overrides any earlier
129 .Fl f
130 and
131 .Fl l
132 options.
133 .It Fl l
134 A synonym for
135 .Fl a .
136 Also reverts any earlier
137 .Fl f
138 and
139 .Fl k
140 options.
141 .It Fl m Ns Ar format
142 Input format.
143 See
144 .Sx Input Formats
145 for available formats.
146 Defaults to
147 .Fl m Ns Cm andoc .
148 .It Fl O Ar option
149 Comma-separated output options.
150 .It Fl T Ar output
151 Output format.
152 See
153 .Sx Output Formats
154 for available formats.
155 Defaults to
156 .Fl T Cm locale .
157 .It Fl W Ar level
158 Specify the minimum message
159 .Ar level
160 to be reported on the standard error output and to affect the exit status.
161 The
162 .Ar level
163 can be
164 .Cm warning ,
165 .Cm error ,
166 or
167 .Cm unsupp ;
168 .Cm all
169 is an alias for
170 .Cm warning .
171 By default,
172 .Nm
173 is silent.
174 See
175 .Sx EXIT STATUS
176 and
177 .Sx DIAGNOSTICS
178 for details.
179 .Pp
180 The special option
181 .Fl W Cm stop
182 tells
183 .Nm
184 to exit after parsing a file that causes warnings or errors of at least
185 the requested level.
186 No formatted output will be produced from that file.
187 If both a
188 .Ar level
189 and
190 .Cm stop
191 are requested, they can be joined with a comma, for example
192 .Fl W Cm error , Ns Cm stop .
193 .It Ar file
194 Read input from zero or more files.
195 If unspecified, reads from stdin.
196 If multiple files are specified,
197 .Nm
198 will halt with the first failed parse.
199 .El
200 .Pp
201 In
202 .Fl f
203 and
204 .Fl k
205 mode,
206 .Nm
207 also supports the options
208 .Fl CMmOSsw
209 described in the
210 .Xr apropos 1
211 manual.
212 .Ss Input Formats
213 The
214 .Nm
215 utility accepts
216 .Xr mdoc 7
217 and
218 .Xr man 7
219 input with
220 .Fl m Ns Cm doc
221 and
222 .Fl m Ns Cm an ,
223 respectively.
224 The
225 .Xr mdoc 7
226 format is
227 .Em strongly
228 recommended;
229 .Xr man 7
230 should only be used for legacy manuals.
231 .Pp
232 A third option,
233 .Fl m Ns Cm andoc ,
234 which is also the default, determines encoding on-the-fly: if the first
235 non-comment macro is
236 .Sq \&Dd
237 or
238 .Sq \&Dt ,
239 the
240 .Xr mdoc 7
241 parser is used; otherwise, the
242 .Xr man 7
243 parser is used.
244 .Pp
245 If multiple
246 files are specified with
247 .Fl m Ns Cm andoc ,
248 each has its file-type determined this way.
249 If multiple files are
250 specified and
251 .Fl m Ns Cm doc
252 or
253 .Fl m Ns Cm an
254 is specified, then this format is used exclusively.
255 .Ss Output Formats
256 The
257 .Nm
258 utility accepts the following
259 .Fl T
260 arguments, which correspond to output modes:
261 .Bl -tag -width "-T markdown"
262 .It Fl T Cm ascii
263 Produce 7-bit ASCII output.
264 See
265 .Sx ASCII Output .
266 .It Fl T Cm html
267 Produce HTML5, CSS1, and MathML output.
268 See
269 .Sx HTML Output .
270 .It Fl T Cm lint
271 Parse only: produce no output.
272 Implies
273 .Fl W Cm warning .
274 .It Fl T Cm locale
275 Encode output using the current locale.
276 This is the default.
277 See
278 .Sx Locale Output .
279 .It Fl T Cm man
280 Produce
281 .Xr man 7
282 format output.
283 See
284 .Sx Man Output .
285 .It Fl T Cm markdown
286 Produce output in
287 .Sy markdown
288 format.
289 See
290 .Sx Markdown Output .
291 .It Fl T Cm pdf
292 Produce PDF output.
293 See
294 .Sx PDF Output .
295 .It Fl T Cm ps
296 Produce PostScript output.
297 See
298 .Sx PostScript Output .
299 .It Fl T Cm tree
300 Produce an indented parse tree.
301 See
302 .Sx Syntax tree output .
303 .It Fl T Cm utf8
304 Encode output in the UTF\-8 multi-byte format.
305 See
306 .Sx UTF\-8 Output .
307 .It Fl T Cm xhtml
308 This is a synonym for
309 .Fl T Cm html .
310 .El
311 .Pp
312 If multiple input files are specified, these will be processed by the
313 corresponding filter in-order.
314 .Ss ASCII Output
315 Output produced by
316 .Fl T Cm ascii
317 is rendered in standard 7-bit ASCII documented in
318 .Xr ascii 7 .
319 .Pp
320 Font styles are applied by using back-spaced encoding such that an
321 underlined character
322 .Sq c
323 is rendered as
324 .Sq _ Ns \e[bs] Ns c ,
325 where
326 .Sq \e[bs]
327 is the back-space character number 8.
328 Emboldened characters are rendered as
329 .Sq c Ns \e[bs] Ns c .
330 .Pp
331 The special characters documented in
332 .Xr mandoc_char 7
333 are rendered best-effort in an ASCII equivalent.
334 .Pp
335 Output width is limited to 78 visible columns unless literal input lines
336 exceed this limit.
337 .Pp
338 The following
339 .Fl O
340 arguments are accepted:
341 .Bl -tag -width Ds
342 .It Cm indent Ns = Ns Ar indent
343 The left margin for normal text is set to
344 .Ar indent
345 blank characters instead of the default of five for
346 .Xr mdoc 7
347 and seven for
348 .Xr man 7 .
349 Increasing this is not recommended; it may result in degraded formatting,
350 for example overfull lines or ugly line breaks.
351 .It Cm width Ns = Ns Ar width
352 The output width is set to
353 .Ar width ,
354 which will normalise to \(>=58.
355 .El
356 .Ss HTML Output
357 Output produced by
358 .Fl T Cm html
359 conforms to HTML5 using optional self-closing tags.
360 Default styles use only CSS1.
361 Equations rendered from
362 .Xr eqn 7
363 blocks use MathML.
364 .Pp
365 The
366 .Pa mandoc.css
367 file documents style-sheet classes available for customising output.
368 If a style-sheet is not specified with
369 .Fl O Cm style ,
370 .Fl T Cm html
371 defaults to simple output (via an embedded style-sheet)
372 readable in any graphical or text-based web
373 browser.
374 .Pp
375 Special characters are rendered in decimal-encoded UTF\-8.
376 .Pp
377 The following
378 .Fl O
379 arguments are accepted:
380 .Bl -tag -width Ds
381 .It Cm fragment
382 Omit the <!DOCTYPE> declaration and the <html>, <head>, and <body>
383 elements and only emit the subtree below the <body> element.
384 The
385 .Cm style
386 argument will be ignored.
387 This is useful when embedding manual content within existing documents.
388 .It Cm includes Ns = Ns Ar fmt
389 The string
390 .Ar fmt ,
391 for example,
392 .Ar ../src/%I.html ,
393 is used as a template for linked header files (usually via the
394 .Sq \&In
395 macro).
396 Instances of
397 .Sq \&%I
398 are replaced with the include filename.
399 The default is not to present a
400 hyperlink.
401 .It Cm man Ns = Ns Ar fmt
402 The string
403 .Ar fmt ,
404 for example,
405 .Ar ../html%S/%N.%S.html ,
406 is used as a template for linked manuals (usually via the
407 .Sq \&Xr
408 macro).
409 Instances of
410 .Sq \&%N
411 and
412 .Sq %S
413 are replaced with the linked manual's name and section, respectively.
414 If no section is included, section 1 is assumed.
415 The default is not to
416 present a hyperlink.
417 .It Cm style Ns = Ns Ar style.css
418 The file
419 .Ar style.css
420 is used for an external style-sheet.
421 This must be a valid absolute or
422 relative URI.
423 .El
424 .Ss Locale Output
425 Locale-depending output encoding is triggered with
426 .Fl T Cm locale .
427 This is the default.
428 .Pp
429 This option is not available on all systems: systems without locale
430 support, or those whose internal representation is not natively UCS-4,
431 will fall back to
432 .Fl T Cm ascii .
433 See
434 .Sx ASCII Output
435 for font style specification and available command-line arguments.
436 .Ss Man Output
437 Translate input format into
438 .Xr man 7
439 output format.
440 This is useful for distributing manual sources to legacy systems
441 lacking
442 .Xr mdoc 7
443 formatters.
444 .Pp
445 If
446 .Xr mdoc 7
447 is passed as input, it is translated into
448 .Xr man 7 .
449 If the input format is
450 .Xr man 7 ,
451 the input is copied to the output, expanding any
452 .Xr roff 7
453 .Sq so
454 requests.
455 The parser is also run, and as usual, the
456 .Fl W
457 level controls which
458 .Sx DIAGNOSTICS
459 are displayed before copying the input to the output.
460 .Ss Markdown Output
461 Translate
462 .Xr mdoc 7
463 input to the
464 .Sy markdown
465 format conforming to
466 .Lk http://daringfireball.net/projects/markdown/syntax.text\
467 "John Gruber's 2004 specification" .
468 .Pp
469 Markdown is a very weak markup language, so all semantic markup is
470 lost, and even part of the presentational markup may be lost.
471 Do not use this as an intermediate step in converting to HTML;
472 instead, use
473 .Fl T Cm html
474 directly.
475 .Pp
476 The
477 .Xr man 7 ,
478 .Xr tbl 7 ,
479 and
480 .Xr eqn 7
481 input languages are not supported by
482 .Fl T Cm markdown
483 output mode.
484 .Ss PDF Output
485 PDF-1.1 output may be generated by
486 .Fl T Cm pdf .
487 See
488 .Sx PostScript Output
489 for
490 .Fl O
491 arguments and defaults.
492 .Ss PostScript Output
493 PostScript
494 .Qq Adobe-3.0
495 Level-2 pages may be generated by
496 .Fl T Cm ps .
497 Output pages default to letter sized and are rendered in the Times font
498 family, 11-point.
499 Margins are calculated as 1/9 the page length and width.
500 Line-height is 1.4m.
501 .Pp
502 Special characters are rendered as in
503 .Sx ASCII Output .
504 .Pp
505 The following
506 .Fl O
507 arguments are accepted:
508 .Bl -tag -width Ds
509 .It Cm paper Ns = Ns Ar name
510 The paper size
511 .Ar name
512 may be one of
513 .Ar a3 ,
514 .Ar a4 ,
515 .Ar a5 ,
516 .Ar legal ,
517 or
518 .Ar letter .
519 You may also manually specify dimensions as
520 .Ar NNxNN ,
521 width by height in millimetres.
522 If an unknown value is encountered,
523 .Ar letter
524 is used.
525 .El
526 .Ss UTF\-8 Output
527 Use
528 .Fl T Cm utf8
529 to force a UTF\-8 locale.
530 See
531 .Sx Locale Output
532 for details and options.
533 .Ss Syntax tree output
534 Use
535 .Fl T Cm tree
536 to show a human readable representation of the syntax tree.
537 It is useful for debugging the source code of manual pages.
538 The exact format is subject to change, so don't write parsers for it.
539 .Pp
540 The first paragraph shows meta data found in the
541 .Xr mdoc 7
542 prologue, on the
543 .Xr man 7
544 .Ic \&TH
545 line, or the fallbacks used.
546 .Pp
547 In the tree dump, each output line shows one syntax tree node.
548 Child nodes are indented with respect to their parent node.
549 The columns are:
550 .Pp
551 .Bl -enum -compact
552 .It
553 For macro nodes, the macro name; for text and
554 .Xr tbl 7
555 nodes, the content.
556 There is a special format for
557 .Xr eqn 7
558 nodes.
559 .It
560 Node type (text, elem, block, head, body, body-end, tail, tbl, eqn).
561 .It
562 Flags:
563 .Bl -dash -compact
564 .It
565 An opening parenthesis if the node is an opening delimiter.
566 .It
567 An asterisk if the node starts a new input line.
568 .It
569 The input line number (starting at one).
570 .It
571 A colon.
572 .It
573 The input column number (starting at one).
574 .It
575 A closing parenthesis if the node is a closing delimiter.
576 .It
577 A full stop if the node ends a sentence.
578 .It
579 BROKEN if the node is a block broken by another block.
580 .It
581 NOSRC if the node is not in the input file,
582 but automatically generated from macros.
583 .It
584 NOPRT if the node is not supposed to generate output
585 for any output format.
586 .El
587 .El
588 .Pp
589 The following
590 .Fl O
591 argument is accepted:
592 .Bl -tag -width Ds
593 .It Cm noval
594 Skip validation and show the unvalidated syntax tree.
595 This can help to find out whether a given behaviour is caused by
596 the parser or by the validator.
597 Meta data is not available in this case.
598 .El
599 .Sh ENVIRONMENT
600 .Bl -tag -width MANPAGER
601 .It Ev MANPAGER
602 Any non-empty value of the environment variable
603 .Ev MANPAGER
604 will be used instead of the standard pagination program,
605 .Xr more 1 .
606 .It Ev PAGER
607 Specifies the pagination program to use when
608 .Ev MANPAGER
609 is not defined.
610 If neither PAGER nor MANPAGER is defined,
611 .Xr more 1
612 .Fl s
613 will be used.
614 .El
615 .Sh EXIT STATUS
616 The
617 .Nm
618 utility exits with one of the following values, controlled by the message
619 .Ar level
620 associated with the
621 .Fl W
622 option:
623 .Pp
624 .Bl -tag -width Ds -compact
625 .It 0
626 No warnings or errors occurred, or those that did were ignored because
627 they were lower than the requested
628 .Ar level .
629 .It 2
630 At least one warning occurred, but no error, and
631 .Fl W Cm warning
632 was specified.
633 .It 3
634 At least one parsing error occurred,
635 but no unsupported feature was encountered, and
636 .Fl W Cm error
637 or
638 .Fl W Cm warning
639 was specified.
640 .It 4
641 At least one unsupported feature was encountered, and
642 .Fl W Cm unsupp ,
643 .Fl W Cm error
644 or
645 .Fl W Cm warning
646 was specified.
647 .It 5
648 Invalid command line arguments were specified.
649 No input files have been read.
650 .It 6
651 An operating system error occurred, for example exhaustion
652 of memory, file descriptors, or process table entries.
653 Such errors cause
654 .Nm
655 to exit at once, possibly in the middle of parsing or formatting a file.
656 .El
657 .Pp
658 Note that selecting
659 .Fl T Cm lint
660 output mode implies
661 .Fl W Cm warning .
662 .Sh EXAMPLES
663 To page manuals to the terminal:
664 .Pp
665 .Dl $ mandoc \-W all,stop mandoc.1 2\*(Gt&1 | less
666 .Dl $ mandoc mandoc.1 mdoc.3 mdoc.7 | less
667 .Pp
668 To produce HTML manuals with
669 .Pa mandoc.css
670 as the style-sheet:
671 .Pp
672 .Dl $ mandoc \-T html -O style=mandoc.css mdoc.7 \*(Gt mdoc.7.html
673 .Pp
674 To check over a large set of manuals:
675 .Pp
676 .Dl $ mandoc \-T lint \(gafind /usr/src -name \e*\e.[1-9]\(ga
677 .Pp
678 To produce a series of PostScript manuals for A4 paper:
679 .Pp
680 .Dl $ mandoc \-T ps \-O paper=a4 mdoc.7 man.7 \*(Gt manuals.ps
681 .Pp
682 Convert a modern
683 .Xr mdoc 7
684 manual to the older
685 .Xr man 7
686 format, for use on systems lacking an
687 .Xr mdoc 7
688 parser:
689 .Pp
690 .Dl $ mandoc \-T man foo.mdoc \*(Gt foo.man
691 .Sh DIAGNOSTICS
692 Messages displayed by
693 .Nm
694 follow this format:
695 .Pp
696 .D1 Nm Ns : Ar file : Ns Ar line : Ns Ar column : level : message : macro args
697 .Pp
698 Line and column numbers start at 1.
699 Both are omitted for messages referring to an input file as a whole.
700 Macro names and arguments are omitted where meaningless.
701 Fatal messages about invalid command line arguments
702 or operating system errors, for example when memory is exhausted,
703 may also omit the
704 .Ar file
705 and
706 .Ar level
707 fields.
708 .Pp
709 Message levels have the following meanings:
710 .Bl -tag -width "warning"
711 .It Cm unsupp
712 An input file uses unsupported low-level
713 .Xr roff 7
714 features.
715 The output may be incomplete and/or misformatted,
716 so using GNU troff instead of
717 .Nm
718 to process the file may be preferable.
719 .It Cm error
720 An input file contains invalid syntax that cannot be safely interpreted.
721 By discarding part of the input or inserting missing tokens,
722 the parser is able to continue, and the error does not prevent
723 generation of formatted output, but typically, preparing that
724 output involves information loss, broken document structure
725 or unintended formatting, no matter whether
726 .Nm
727 or GNU troff is used.
728 In many cases, the output of
729 .Nm
730 and GNU troff is identical, but in some,
731 .Nm
732 is more resilient than GNU troff with respect to malformed input.
733 .Pp
734 Non-existent or unreadable input files are also reported on the
735 .Cm error
736 level.
737 In that case, the parser cannot even be started and no output
738 is produced from those input files.
739 .It Cm warning
740 An input file uses obsolete, discouraged or non-portable syntax.
741 All the same, the meaning of the input is unambiguous and a correct
742 rendering can be produced.
743 Documents causing warnings may render poorly when using other
744 formatting tools instead of
745 .Nm .
746 .El
747 .Pp
748 Messages of the
749 .Cm warning ,
750 .Cm error ,
751 and
752 .Cm unsupp
753 levels except those about non-existent or unreadable input files
754 are hidden unless their level, or a lower level, is requested using a
755 .Fl W
756 option or
757 .Fl T Cm lint
758 output mode.
759 .Ss Warnings related to the document prologue
760 .Bl -ohang
761 .It Sy "missing manual title, using UNTITLED"
762 .Pq mdoc
763 A
764 .Ic \&Dt
765 macro has no arguments, or there is no
766 .Ic \&Dt
767 macro before the first non-prologue macro.
768 .It Sy "missing manual title, using \(dq\(dq"
769 .Pq man
770 There is no
771 .Ic \&TH
772 macro, or it has no arguments.
773 .It Sy "lower case character in document title"
774 .Pq mdoc , man
775 The title is still used as given in the
776 .Ic \&Dt
777 or
778 .Ic \&TH
779 macro.
780 .It Sy "missing manual section, using \(dq\(dq"
781 .Pq mdoc , man
782 A
783 .Ic \&Dt
784 or
785 .Ic \&TH
786 macro lacks the mandatory section argument.
787 .It Sy "unknown manual section"
788 .Pq mdoc
789 The section number in a
790 .Ic \&Dt
791 line is invalid, but still used.
792 .It Sy "missing date, using today's date"
793 .Pq mdoc, man
794 The document was parsed as
795 .Xr mdoc 7
796 and it has no
797 .Ic \&Dd
798 macro, or the
799 .Ic \&Dd
800 macro has no arguments or only empty arguments;
801 or the document was parsed as
802 .Xr man 7
803 and it has no
804 .Ic \&TH
805 macro, or the
806 .Ic \&TH
807 macro has less than three arguments or its third argument is empty.
808 .It Sy "cannot parse date, using it verbatim"
809 .Pq mdoc , man
810 The date given in a
811 .Ic \&Dd
812 or
813 .Ic \&TH
814 macro does not follow the conventional format.
815 .It Sy "missing Os macro, using \(dq\(dq"
816 .Pq mdoc
817 The default or current system is not shown in this case.
818 .It Sy "duplicate prologue macro"
819 .Pq mdoc
820 One of the prologue macros occurs more than once.
821 The last instance overrides all previous ones.
822 .It Sy "late prologue macro"
823 .Pq mdoc
824 A
825 .Ic \&Dd
826 or
827 .Ic \&Os
828 macro occurs after some non-prologue macro, but still takes effect.
829 .It Sy "skipping late title macro"
830 .Pq mdoc
831 The
832 .Ic \&Dt
833 macro appears after the first non-prologue macro.
834 Traditional formatters cannot handle this because
835 they write the page header before parsing the document body.
836 Even though this technical restriction does not apply to
837 .Nm ,
838 traditional semantics is preserved.
839 The late macro is discarded including its arguments.
840 .It Sy "prologue macros out of order"
841 .Pq mdoc
842 The prologue macros are not given in the conventional order
843 .Ic \&Dd ,
844 .Ic \&Dt ,
845 .Ic \&Os .
846 All three macros are used even when given in another order.
847 .El
848 .Ss Warnings regarding document structure
849 .Bl -ohang
850 .It Sy ".so is fragile, better use ln(1)"
851 .Pq roff
852 Including files only works when the parser program runs with the correct
853 current working directory.
854 .It Sy "no document body"
855 .Pq mdoc , man
856 The document body contains neither text nor macros.
857 An empty document is shown, consisting only of a header and a footer line.
858 .It Sy "content before first section header"
859 .Pq mdoc , man
860 Some macros or text precede the first
861 .Ic \&Sh
862 or
863 .Ic \&SH
864 section header.
865 The offending macros and text are parsed and added to the top level
866 of the syntax tree, outside any section block.
867 .It Sy "first section is not NAME"
868 .Pq mdoc
869 The argument of the first
870 .Ic \&Sh
871 macro is not
872 .Sq NAME .
873 This may confuse
874 .Xr makewhatis 8
875 and
876 .Xr apropos 1 .
877 .It Sy "NAME section without Nm before Nd"
878 .Pq mdoc
879 The NAME section does not contain any
880 .Ic \&Nm
881 child macro before the first
882 .Ic \&Nd
883 macro.
884 .It Sy "NAME section without description"
885 .Pq mdoc
886 The NAME section lacks the mandatory
887 .Ic \&Nd
888 child macro.
889 .It Sy "description not at the end of NAME"
890 .Pq mdoc
891 The NAME section does contain an
892 .Ic \&Nd
893 child macro, but other content follows it.
894 .It Sy "bad NAME section content"
895 .Pq mdoc
896 The NAME section contains plain text or macros other than
897 .Ic \&Nm
898 and
899 .Ic \&Nd .
900 .It Sy "missing comma before name"
901 .Pq mdoc
902 The NAME section contains an
903 .Ic \&Nm
904 macro that is neither the first one nor preceded by a comma.
905 .It Sy "missing description line, using \(dq\(dq"
906 .Pq mdoc
907 The
908 .Ic \&Nd
909 macro lacks the required argument.
910 The title line of the manual will end after the dash.
911 .It Sy "sections out of conventional order"
912 .Pq mdoc
913 A standard section occurs after another section it usually precedes.
914 All section titles are used as given,
915 and the order of sections is not changed.
916 .It Sy "duplicate section title"
917 .Pq mdoc
918 The same standard section title occurs more than once.
919 .It Sy "unexpected section"
920 .Pq mdoc
921 A standard section header occurs in a section of the manual
922 where it normally isn't useful.
923 .It Sy "unusual Xr order"
924 .Pq mdoc
925 In the SEE ALSO section, an
926 .Ic \&Xr
927 macro with a lower section number follows one with a higher number,
928 or two
929 .Ic \&Xr
930 macros referring to the same section are out of alphabetical order.
931 .It Sy "unusual Xr punctuation"
932 .Pq mdoc
933 In the SEE ALSO section, punctuation between two
934 .Ic \&Xr
935 macros differs from a single comma, or there is trailing punctuation
936 after the last
937 .Ic \&Xr
938 macro.
939 .It Sy "AUTHORS section without An macro"
940 .Pq mdoc
941 An AUTHORS sections contains no
942 .Ic \&An
943 macros, or only empty ones.
944 Probably, there are author names lacking markup.
945 .El
946 .Ss "Warnings related to macros and nesting"
947 .Bl -ohang
948 .It Sy "obsolete macro"
949 .Pq mdoc
950 See the
951 .Xr mdoc 7
952 manual for replacements.
953 .It Sy "macro neither callable nor escaped"
954 .Pq mdoc
955 The name of a macro that is not callable appears on a macro line.
956 It is printed verbatim.
957 If the intention is to call it, move it to its own input line;
958 otherwise, escape it by prepending
959 .Sq \e& .
960 .It Sy "skipping paragraph macro"
961 In
962 .Xr mdoc 7
963 documents, this happens
964 .Bl -dash -compact
965 .It
966 at the beginning and end of sections and subsections
967 .It
968 right before non-compact lists and displays
969 .It
970 at the end of items in non-column, non-compact lists
971 .It
972 and for multiple consecutive paragraph macros.
973 .El
974 In
975 .Xr man 7
976 documents, it happens
977 .Bl -dash -compact
978 .It
979 for empty
980 .Ic \&P ,
981 .Ic \&PP ,
982 and
983 .Ic \&LP
984 macros
985 .It
986 for
987 .Ic \&IP
988 macros having neither head nor body arguments
989 .It
990 for
991 .Ic \&br
992 or
993 .Ic \&sp
994 right after
995 .Ic \&SH
996 or
997 .Ic \&SS
998 .El
999 .It Sy "moving paragraph macro out of list"
1000 .Pq mdoc
1001 A list item in a
1002 .Ic \&Bl
1003 list contains a trailing paragraph macro.
1004 The paragraph macro is moved after the end of the list.
1005 .It Sy "skipping no-space macro"
1006 .Pq mdoc
1007 An input line begins with an
1008 .Ic \&Ns
1009 macro.
1010 The macro is ignored.
1011 .It Sy "blocks badly nested"
1012 .Pq mdoc
1013 If two blocks intersect, one should completely contain the other.
1014 Otherwise, rendered output is likely to look strange in any output
1015 format, and rendering in SGML-based output formats is likely to be
1016 outright wrong because such languages do not support badly nested
1017 blocks at all.
1018 Typical examples of badly nested blocks are
1019 .Qq Ic \&Ao \&Bo \&Ac \&Bc
1020 and
1021 .Qq Ic \&Ao \&Bq \&Ac .
1022 In these examples,
1023 .Ic \&Ac
1024 breaks
1025 .Ic \&Bo
1026 and
1027 .Ic \&Bq ,
1028 respectively.
1029 .It Sy "nested displays are not portable"
1030 .Pq mdoc
1031 A
1032 .Ic \&Bd ,
1033 .Ic \&D1 ,
1034 or
1035 .Ic \&Dl
1036 display occurs nested inside another
1037 .Ic \&Bd
1038 display.
1039 This works with
1040 .Nm ,
1041 but fails with most other implementations.
1042 .It Sy "moving content out of list"
1043 .Pq mdoc
1044 A
1045 .Ic \&Bl
1046 list block contains text or macros before the first
1047 .Ic \&It
1048 macro.
1049 The offending children are moved before the beginning of the list.
1050 .It Sy "fill mode already enabled, skipping"
1051 .Pq man
1052 A
1053 .Ic \&fi
1054 request occurs even though the document is still in fill mode,
1055 or already switched back to fill mode.
1056 It has no effect.
1057 .It Sy "fill mode already disabled, skipping"
1058 .Pq man
1059 An
1060 .Ic \&nf
1061 request occurs even though the document already switched to no-fill mode
1062 and did not switch back to fill mode yet.
1063 It has no effect.
1064 .It Sy "line scope broken"
1065 .Pq man
1066 While parsing the next-line scope of the previous macro,
1067 another macro is found that prematurely terminates the previous one.
1068 The previous, interrupted macro is deleted from the parse tree.
1069 .El
1070 .Ss "Warnings related to missing arguments"
1071 .Bl -ohang
1072 .It Sy "skipping empty request"
1073 .Pq roff , eqn
1074 The macro name is missing from a macro definition request,
1075 or an
1076 .Xr eqn 7
1077 control statement or operation keyword lacks its required argument.
1078 .It Sy "conditional request controls empty scope"
1079 .Pq roff
1080 A conditional request is only useful if any of the following
1081 follows it on the same logical input line:
1082 .Bl -dash -compact
1083 .It
1084 The
1085 .Sq \e{
1086 keyword to open a multi-line scope.
1087 .It
1088 A request or macro or some text, resulting in a single-line scope.
1089 .It
1090 The immediate end of the logical line without any intervening whitespace,
1091 resulting in next-line scope.
1092 .El
1093 Here, a conditional request is followed by trailing whitespace only,
1094 and there is no other content on its logical input line.
1095 Note that it doesn't matter whether the logical input line is split
1096 across multiple physical input lines using
1097 .Sq \e
1098 line continuation characters.
1099 This is one of the rare cases
1100 where trailing whitespace is syntactically significant.
1101 The conditional request controls a scope containing whitespace only,
1102 so it is unlikely to have a significant effect,
1103 except that it may control a following
1104 .Ic \&el
1105 clause.
1106 .It Sy "skipping empty macro"
1107 .Pq mdoc
1108 The indicated macro has no arguments and hence no effect.
1109 .It Sy "empty block"
1110 .Pq mdoc , man
1111 A
1112 .Ic \&Bd ,
1113 .Ic \&Bk ,
1114 .Ic \&Bl ,
1115 .Ic \&D1 ,
1116 .Ic \&Dl ,
1117 .Ic \&RS ,
1118 or
1119 .Ic \&UR
1120 block contains nothing in its body and will produce no output.
1121 .It Sy "empty argument, using 0n"
1122 .Pq mdoc
1123 The required width is missing after
1124 .Ic \&Bd
1125 or
1126 .Ic \&Bl
1127 .Fl offset
1128 or
1129 .Fl width.
1130 .It Sy "missing display type, using -ragged"
1131 .Pq mdoc
1132 The
1133 .Ic \&Bd
1134 macro is invoked without the required display type.
1135 .It Sy "list type is not the first argument"
1136 .Pq mdoc
1137 In a
1138 .Ic \&Bl
1139 macro, at least one other argument precedes the type argument.
1140 The
1141 .Nm
1142 utility copes with any argument order, but some other
1143 .Xr mdoc 7
1144 implementations do not.
1145 .It Sy "missing -width in -tag list, using 8n"
1146 .Pq mdoc
1147 Every
1148 .Ic \&Bl
1149 macro having the
1150 .Fl tag
1151 argument requires
1152 .Fl width ,
1153 too.
1154 .It Sy "missing utility name, using \(dq\(dq"
1155 .Pq mdoc
1156 The
1157 .Ic \&Ex Fl std
1158 macro is called without an argument before
1159 .Ic \&Nm
1160 has first been called with an argument.
1161 .It Sy "missing function name, using \(dq\(dq"
1162 .Pq mdoc
1163 The
1164 .Ic \&Fo
1165 macro is called without an argument.
1166 No function name is printed.
1167 .It Sy "empty head in list item"
1168 .Pq mdoc
1169 In a
1170 .Ic \&Bl
1171 .Fl diag ,
1172 .Fl hang ,
1173 .Fl inset ,
1174 .Fl ohang ,
1175 or
1176 .Fl tag
1177 list, an
1178 .Ic \&It
1179 macro lacks the required argument.
1180 The item head is left empty.
1181 .It Sy "empty list item"
1182 .Pq mdoc
1183 In a
1184 .Ic \&Bl
1185 .Fl bullet ,
1186 .Fl dash ,
1187 .Fl enum ,
1188 or
1189 .Fl hyphen
1190 list, an
1191 .Ic \&It
1192 block is empty.
1193 An empty list item is shown.
1194 .It Sy "missing font type, using \efR"
1195 .Pq mdoc
1196 A
1197 .Ic \&Bf
1198 macro has no argument.
1199 It switches to the default font.
1200 .It Sy "unknown font type, using \efR"
1201 .Pq mdoc
1202 The
1203 .Ic \&Bf
1204 argument is invalid.
1205 The default font is used instead.
1206 .It Sy "nothing follows prefix"
1207 .Pq mdoc
1208 A
1209 .Ic \&Pf
1210 macro has no argument, or only one argument and no macro follows
1211 on the same input line.
1212 This defeats its purpose; in particular, spacing is not suppressed
1213 before the text or macros following on the next input line.
1214 .It Sy "empty reference block"
1215 .Pq mdoc
1216 An
1217 .Ic \&Rs
1218 macro is immediately followed by an
1219 .Ic \&Re
1220 macro on the next input line.
1221 Such an empty block does not produce any output.
1222 .It Sy "missing section argument"
1223 .Pq mdoc
1224 An
1225 .Ic \&Xr
1226 macro lacks its second, section number argument.
1227 The first argument, i.e. the name, is printed, but without subsequent
1228 parentheses.
1229 .It Sy "missing -std argument, adding it"
1230 .Pq mdoc
1231 An
1232 .Ic \&Ex
1233 or
1234 .Ic \&Rv
1235 macro lacks the required
1236 .Fl std
1237 argument.
1238 The
1239 .Nm
1240 utility assumes
1241 .Fl std
1242 even when it is not specified, but other implementations may not.
1243 .It Sy "missing option string, using \(dq\(dq"
1244 .Pq man
1245 The
1246 .Ic \&OP
1247 macro is invoked without any argument.
1248 An empty pair of square brackets is shown.
1249 .It Sy "missing resource identifier, using \(dq\(dq"
1250 .Pq man
1251 The
1252 .Ic \&UR
1253 macro is invoked without any argument.
1254 An empty pair of angle brackets is shown.
1255 .It Sy "missing eqn box, using \(dq\(dq"
1256 .Pq eqn
1257 A diacritic mark or a binary operator is found,
1258 but there is nothing to the left of it.
1259 An empty box is inserted.
1260 .El
1261 .Ss "Warnings related to bad macro arguments"
1262 .Bl -ohang
1263 .It Sy "unterminated quoted argument"
1264 .Pq roff
1265 Macro arguments can be enclosed in double quote characters
1266 such that space characters and macro names contained in the quoted
1267 argument need not be escaped.
1268 The closing quote of the last argument of a macro can be omitted.
1269 However, omitting it is not recommended because it makes the code
1270 harder to read.
1271 .It Sy "duplicate argument"
1272 .Pq mdoc
1273 A
1274 .Ic \&Bd
1275 or
1276 .Ic \&Bl
1277 macro has more than one
1278 .Fl compact ,
1279 more than one
1280 .Fl offset ,
1281 or more than one
1282 .Fl width
1283 argument.
1284 All but the last instances of these arguments are ignored.
1285 .It Sy "skipping duplicate argument"
1286 .Pq mdoc
1287 An
1288 .Ic \&An
1289 macro has more than one
1290 .Fl split
1291 or
1292 .Fl nosplit
1293 argument.
1294 All but the first of these arguments are ignored.
1295 .It Sy "skipping duplicate display type"
1296 .Pq mdoc
1297 A
1298 .Ic \&Bd
1299 macro has more than one type argument; the first one is used.
1300 .It Sy "skipping duplicate list type"
1301 .Pq mdoc
1302 A
1303 .Ic \&Bl
1304 macro has more than one type argument; the first one is used.
1305 .It Sy "skipping -width argument"
1306 .Pq mdoc
1307 A
1308 .Ic \&Bl
1309 .Fl column ,
1310 .Fl diag ,
1311 .Fl ohang ,
1312 .Fl inset ,
1313 or
1314 .Fl item
1315 list has a
1316 .Fl width
1317 argument.
1318 That has no effect.
1319 .It Sy "wrong number of cells"
1320 In a line of a
1321 .Ic \&Bl Fl column
1322 list, the number of tabs or
1323 .Ic \&Ta
1324 macros is less than the number expected from the list header line
1325 or exceeds the expected number by more than one.
1326 Missing cells remain empty, and all cells exceeding the number of
1327 columns are joined into one single cell.
1328 .It Sy "unknown AT&T UNIX version"
1329 .Pq mdoc
1330 An
1331 .Ic \&At
1332 macro has an invalid argument.
1333 It is used verbatim, with
1334 .Qq "AT&T UNIX "
1335 prefixed to it.
1336 .It Sy "comma in function argument"
1337 .Pq mdoc
1338 An argument of an
1339 .Ic \&Fa
1340 or
1341 .Ic \&Fn
1342 macro contains a comma; it should probably be split into two arguments.
1343 .It Sy "parenthesis in function name"
1344 .Pq mdoc
1345 The first argument of an
1346 .Ic \&Fc
1347 or
1348 .Ic \&Fn
1349 macro contains an opening or closing parenthesis; that's probably wrong,
1350 parentheses are added automatically.
1351 .It Sy "invalid content in Rs block"
1352 .Pq mdoc
1353 An
1354 .Ic \&Rs
1355 block contains plain text or non-% macros.
1356 The bogus content is left in the syntax tree.
1357 Formatting may be poor.
1358 .It Sy "invalid Boolean argument"
1359 .Pq mdoc
1360 An
1361 .Ic \&Sm
1362 macro has an argument other than
1363 .Cm on
1364 or
1365 .Cm off .
1366 The invalid argument is moved out of the macro, which leaves the macro
1367 empty, causing it to toggle the spacing mode.
1368 .It Sy "unknown font, skipping request"
1369 .Pq man , tbl
1370 A
1371 .Xr roff 7
1372 .Ic \&ft
1373 request or a
1374 .Xr tbl 7
1375 .Ic \&f
1376 layout modifier has an unknown
1377 .Ar font
1378 argument.
1379 .It Sy "odd number of characters in request"
1380 .Pq roff
1381 A
1382 .Ic \&tr
1383 request contains an odd number of characters.
1384 The last character is mapped to the blank character.
1385 .El
1386 .Ss "Warnings related to plain text"
1387 .Bl -ohang
1388 .It Sy "blank line in fill mode, using .sp"
1389 .Pq mdoc
1390 The meaning of blank input lines is only well-defined in non-fill mode:
1391 In fill mode, line breaks of text input lines are not supposed to be
1392 significant.
1393 However, for compatibility with groff, blank lines in fill mode
1394 are replaced with
1395 .Ic \&sp
1396 requests.
1397 .It Sy "tab in filled text"
1398 .Pq mdoc , man
1399 The meaning of tab characters is only well-defined in non-fill mode:
1400 In fill mode, whitespace is not supposed to be significant
1401 on text input lines.
1402 As an implementation dependent choice, tab characters on text lines
1403 are passed through to the formatters in any case.
1404 Given that the text before the tab character will be filled,
1405 it is hard to predict which tab stop position the tab will advance to.
1406 .It Sy "whitespace at end of input line"
1407 .Pq mdoc , man , roff
1408 Whitespace at the end of input lines is almost never semantically
1409 significant \(em but in the odd case where it might be, it is
1410 extremely confusing when reviewing and maintaining documents.
1411 .It Sy "new sentence, new line"
1412 .Pq mdoc
1413 A new sentence starts in the middle of a text line.
1414 Start it on a new input line to help formatters produce correct spacing.
1415 .It Sy "bad comment style"
1416 .Pq roff
1417 Comment lines start with a dot, a backslash, and a double-quote character.
1418 The
1419 .Nm
1420 utility treats the line as a comment line even without the backslash,
1421 but leaving out the backslash might not be portable.
1422 .It Sy "invalid escape sequence"
1423 .Pq roff
1424 An escape sequence has an invalid opening argument delimiter, lacks the
1425 closing argument delimiter, or the argument has too few characters.
1426 If the argument is incomplete,
1427 .Ic \e*
1428 and
1429 .Ic \en
1430 expand to an empty string,
1431 .Ic \eB
1432 to the digit
1433 .Sq 0 ,
1434 and
1435 .Ic \ew
1436 to the length of the incomplete argument.
1437 All other invalid escape sequences are ignored.
1438 .It Sy "undefined string, using \(dq\(dq"
1439 .Pq roff
1440 If a string is used without being defined before,
1441 its value is implicitly set to the empty string.
1442 However, defining strings explicitly before use
1443 keeps the code more readable.
1444 .El
1445 .Ss "Warnings related to tables"
1446 .Bl -ohang
1447 .It Sy "tbl line starts with span"
1448 .Pq tbl
1449 The first cell in a table layout line is a horizontal span
1450 .Pq Sq Cm s .
1451 Data provided for this cell is ignored, and nothing is printed in the cell.
1452 .It Sy "tbl column starts with span"
1453 .Pq tbl
1454 The first line of a table layout specification
1455 requests a vertical span
1456 .Pq Sq Cm ^ .
1457 Data provided for this cell is ignored, and nothing is printed in the cell.
1458 .It Sy "skipping vertical bar in tbl layout"
1459 .Pq tbl
1460 A table layout specification contains more than two consecutive vertical bars.
1461 A double bar is printed, all additional bars are discarded.
1462 .El
1463 .Ss "Errors related to tables"
1464 .Bl -ohang
1465 .It Sy "non-alphabetic character in tbl options"
1466 .Pq tbl
1467 The table options line contains a character other than a letter,
1468 blank, or comma where the beginning of an option name is expected.
1469 The character is ignored.
1470 .It Sy "skipping unknown tbl option"
1471 .Pq tbl
1472 The table options line contains a string of letters that does not
1473 match any known option name.
1474 The word is ignored.
1475 .It Sy "missing tbl option argument"
1476 .Pq tbl
1477 A table option that requires an argument is not followed by an
1478 opening parenthesis, or the opening parenthesis is immediately
1479 followed by a closing parenthesis.
1480 The option is ignored.
1481 .It Sy "wrong tbl option argument size"
1482 .Pq tbl
1483 A table option argument contains an invalid number of characters.
1484 Both the option and the argument are ignored.
1485 .It Sy "empty tbl layout"
1486 .Pq tbl
1487 A table layout specification is completely empty,
1488 specifying zero lines and zero columns.
1489 As a fallback, a single left-justified column is used.
1490 .It Sy "invalid character in tbl layout"
1491 .Pq tbl
1492 A table layout specification contains a character that can neither
1493 be interpreted as a layout key character nor as a layout modifier,
1494 or a modifier precedes the first key.
1495 The invalid character is discarded.
1496 .It Sy "unmatched parenthesis in tbl layout"
1497 .Pq tbl
1498 A table layout specification contains an opening parenthesis,
1499 but no matching closing parenthesis.
1500 The rest of the input line, starting from the parenthesis, has no effect.
1501 .It Sy "tbl without any data cells"
1502 .Pq tbl
1503 A table does not contain any data cells.
1504 It will probably produce no output.
1505 .It Sy "ignoring data in spanned tbl cell"
1506 .Pq tbl
1507 A table cell is marked as a horizontal span
1508 .Pq Sq Cm s
1509 or vertical span
1510 .Pq Sq Cm ^
1511 in the table layout, but it contains data.
1512 The data is ignored.
1513 .It Sy "ignoring extra tbl data cells"
1514 .Pq tbl
1515 A data line contains more cells than the corresponding layout line.
1516 The data in the extra cells is ignored.
1517 .It Sy "data block open at end of tbl"
1518 .Pq tbl
1519 A data block is opened with
1520 .Cm T{ ,
1521 but never closed with a matching
1522 .Cm T} .
1523 The remaining data lines of the table are all put into one cell,
1524 and any remaining cells stay empty.
1525 .El
1526 .Ss "Errors related to roff, mdoc, and man code"
1527 .Bl -ohang
1528 .It Sy "input stack limit exceeded, infinite loop?"
1529 .Pq roff
1530 Explicit recursion limits are implemented for the following features,
1531 in order to prevent infinite loops:
1532 .Bl -dash -compact
1533 .It
1534 expansion of nested escape sequences
1535 including expansion of strings and number registers,
1536 .It
1537 expansion of nested user-defined macros,
1538 .It
1539 and
1540 .Ic \&so
1541 file inclusion.
1542 .El
1543 When a limit is hit, the output is incorrect, typically losing
1544 some content, but the parser can continue.
1545 .It Sy "skipping bad character"
1546 .Pq mdoc , man , roff
1547 The input file contains a byte that is not a printable
1548 .Xr ascii 7
1549 character.
1550 The message mentions the character number.
1551 The offending byte is replaced with a question mark
1552 .Pq Sq \&? .
1553 Consider editing the input file to replace the byte with an ASCII
1554 transliteration of the intended character.
1555 .It Sy "skipping unknown macro"
1556 .Pq mdoc , man , roff
1557 The first identifier on a request or macro line is neither recognized as a
1558 .Xr roff 7
1559 request, nor as a user-defined macro, nor, respectively, as an
1560 .Xr mdoc 7
1561 or
1562 .Xr man 7
1563 macro.
1564 It may be mistyped or unsupported.
1565 The request or macro is discarded including its arguments.
1566 .It Sy "skipping insecure request"
1567 .Pq roff
1568 An input file attempted to run a shell command
1569 or to read or write an external file.
1570 Such attempts are denied for security reasons.
1571 .It Sy "skipping item outside list"
1572 .Pq mdoc , eqn
1573 An
1574 .Ic \&It
1575 macro occurs outside any
1576 .Ic \&Bl
1577 list, or an
1578 .Xr eqn 7
1579 .Ic above
1580 delimiter occurs outside any pile.
1581 It is discarded including its arguments.
1582 .It Sy "skipping column outside column list"
1583 .Pq mdoc
1584 A
1585 .Ic \&Ta
1586 macro occurs outside any
1587 .Ic \&Bl Fl column
1588 block.
1589 It is discarded including its arguments.
1590 .It Sy "skipping end of block that is not open"
1591 .Pq mdoc , man , eqn , tbl , roff
1592 Various syntax elements can only be used to explicitly close blocks
1593 that have previously been opened.
1594 An
1595 .Xr mdoc 7
1596 block closing macro, a
1597 .Xr man 7
1598 .Ic \&RE
1599 or
1600 .Ic \&UE
1601 macro, an
1602 .Xr eqn 7
1603 right delimiter or closing brace, or the end of an equation, table, or
1604 .Xr roff 7
1605 conditional request is encountered but no matching block is open.
1606 The offending request or macro is discarded.
1607 .It Sy "fewer RS blocks open, skipping"
1608 .Pq man
1609 The
1610 .Ic \&RE
1611 macro is invoked with an argument, but less than the specified number of
1612 .Ic \&RS
1613 blocks is open.
1614 The
1615 .Ic \&RE
1616 macro is discarded.
1617 .It Sy "inserting missing end of block"
1618 .Pq mdoc , tbl
1619 Various
1620 .Xr mdoc 7
1621 macros as well as tables require explicit closing by dedicated macros.
1622 A block that doesn't support bad nesting
1623 ends before all of its children are properly closed.
1624 The open child nodes are closed implicitly.
1625 .It Sy "appending missing end of block"
1626 .Pq mdoc , man , eqn , tbl , roff
1627 At the end of the document, an explicit
1628 .Xr mdoc 7
1629 block, a
1630 .Xr man 7
1631 next-line scope or
1632 .Ic \&RS
1633 or
1634 .Ic \&UR
1635 block, an equation, table, or
1636 .Xr roff 7
1637 conditional or ignore block is still open.
1638 The open block is closed implicitly.
1639 .It Sy "escaped character not allowed in a name"
1640 .Pq roff
1641 Macro, string and register identifiers consist of printable,
1642 non-whitespace ASCII characters.
1643 Escape sequences and characters and strings expressed in terms of them
1644 cannot form part of a name.
1645 The first argument of an
1646 .Ic \&am ,
1647 .Ic \&as ,
1648 .Ic \&de ,
1649 .Ic \&ds ,
1650 .Ic \&nr ,
1651 or
1652 .Ic \&rr
1653 request, or any argument of an
1654 .Ic \&rm
1655 request, or the name of a request or user defined macro being called,
1656 is terminated by an escape sequence.
1657 In the cases of
1658 .Ic \&as ,
1659 .Ic \&ds ,
1660 and
1661 .Ic \&nr ,
1662 the request has no effect at all.
1663 In the cases of
1664 .Ic \&am ,
1665 .Ic \&de ,
1666 .Ic \&rr ,
1667 and
1668 .Ic \&rm ,
1669 what was parsed up to this point is used as the arguments to the request,
1670 and the rest of the input line is discarded including the escape sequence.
1671 When parsing for a request or a user-defined macro name to be called,
1672 only the escape sequence is discarded.
1673 The characters preceding it are used as the request or macro name,
1674 the characters following it are used as the arguments to the request or macro.
1675 .It Sy "NOT IMPLEMENTED: Bd -file"
1676 .Pq mdoc
1677 For security reasons, the
1678 .Ic \&Bd
1679 macro does not support the
1680 .Fl file
1681 argument.
1682 By requesting the inclusion of a sensitive file, a malicious document
1683 might otherwise trick a privileged user into inadvertently displaying
1684 the file on the screen, revealing the file content to bystanders.
1685 The argument is ignored including the file name following it.
1686 .It Sy "skipping display without arguments"
1687 .Pq mdoc
1688 A
1689 .Ic \&Bd
1690 block macro does not have any arguments.
1691 The block is discarded, and the block content is displayed in
1692 whatever mode was active before the block.
1693 .It Sy "missing list type, using -item"
1694 .Pq mdoc
1695 A
1696 .Ic \&Bl
1697 macro fails to specify the list type.
1698 .It Sy "missing manual name, using \(dq\(dq"
1699 .Pq mdoc
1700 The first call to
1701 .Ic \&Nm ,
1702 or any call in the NAME section, lacks the required argument.
1703 .It Sy "uname(3) system call failed, using UNKNOWN"
1704 .Pq mdoc
1705 The
1706 .Ic \&Os
1707 macro is called without arguments, and the
1708 .Xr uname 3
1709 system call failed.
1710 As a workaround,
1711 .Nm
1712 can be compiled with
1713 .Sm off
1714 .Fl D Cm OSNAME=\(dq\e\(dq Ar string Cm \e\(dq\(dq .
1715 .Sm on
1716 .It Sy "unknown standard specifier"
1717 .Pq mdoc
1718 An
1719 .Ic \&St
1720 macro has an unknown argument and is discarded.
1721 .It Sy "skipping request without numeric argument"
1722 .Pq roff , eqn
1723 An
1724 .Ic \&it
1725 request or an
1726 .Xr eqn 7
1727 .Ic \&size
1728 or
1729 .Ic \&gsize
1730 statement has a non-numeric or negative argument or no argument at all.
1731 The invalid request or statement is ignored.
1732 .It Sy "NOT IMPLEMENTED: .so with absolute path or \(dq..\(dq"
1733 .Pq roff
1734 For security reasons,
1735 .Nm
1736 allows
1737 .Ic \&so
1738 file inclusion requests only with relative paths
1739 and only without ascending to any parent directory.
1740 By requesting the inclusion of a sensitive file, a malicious document
1741 might otherwise trick a privileged user into inadvertently displaying
1742 the file on the screen, revealing the file content to bystanders.
1743 .Nm
1744 only shows the path as it appears behind
1745 .Ic \&so .
1746 .It Sy ".so request failed"
1747 .Pq roff
1748 Servicing a
1749 .Ic \&so
1750 request requires reading an external file, but the file could not be
1751 opened.
1752 .Nm
1753 only shows the path as it appears behind
1754 .Ic \&so .
1755 .It Sy "skipping all arguments"
1756 .Pq mdoc , man , eqn , roff
1757 An
1758 .Xr mdoc 7
1759 .Ic \&Bt ,
1760 .Ic \&Ed ,
1761 .Ic \&Ef ,
1762 .Ic \&Ek ,
1763 .Ic \&El ,
1764 .Ic \&Lp ,
1765 .Ic \&Pp ,
1766 .Ic \&Re ,
1767 .Ic \&Rs ,
1768 or
1769 .Ic \&Ud
1770 macro, an
1771 .Ic \&It
1772 macro in a list that don't support item heads, a
1773 .Xr man 7
1774 .Ic \&LP ,
1775 .Ic \&P ,
1776 or
1777 .Ic \&PP
1778 macro, an
1779 .Xr eqn 7
1780 .Ic \&EQ
1781 or
1782 .Ic \&EN
1783 macro, or a
1784 .Xr roff 7
1785 .Ic \&br ,
1786 .Ic \&fi ,
1787 or
1788 .Ic \&nf
1789 request or
1790 .Sq \&..
1791 block closing request is invoked with at least one argument.
1792 All arguments are ignored.
1793 .It Sy "skipping excess arguments"
1794 .Pq mdoc , man , roff
1795 A macro or request is invoked with too many arguments:
1796 .Bl -dash -offset 2n -width 2n -compact
1797 .It
1798 .Ic \&Fo ,
1799 .Ic \&PD ,
1800 .Ic \&RS ,
1801 .Ic \&UR ,
1802 .Ic \&ft ,
1803 or
1804 .Ic \&sp
1805 with more than one argument
1806 .It
1807 .Ic \&An
1808 with another argument after
1809 .Fl split
1810 or
1811 .Fl nosplit
1812 .It
1813 .Ic \&RE
1814 with more than one argument or with a non-integer argument
1815 .It
1816 .Ic \&OP
1817 or a request of the
1818 .Ic \&de
1819 family with more than two arguments
1820 .It
1821 .Ic \&Dt
1822 with more than three arguments
1823 .It
1824 .Ic \&TH
1825 with more than five arguments
1826 .It
1827 .Ic \&Bd ,
1828 .Ic \&Bk ,
1829 or
1830 .Ic \&Bl
1831 with invalid arguments
1832 .El
1833 The excess arguments are ignored.
1834 .El
1835 .Ss Unsupported features
1836 .Bl -ohang
1837 .It Sy "input too large"
1838 .Pq mdoc , man
1839 Currently,
1840 .Nm
1841 cannot handle input files larger than its arbitrary size limit
1842 of 2^31 bytes (2 Gigabytes).
1843 Since useful manuals are always small, this is not a problem in practice.
1844 Parsing is aborted as soon as the condition is detected.
1845 .It Sy "unsupported control character"
1846 .Pq roff
1847 An ASCII control character supported by other
1848 .Xr roff 7
1849 implementations but not by
1850 .Nm
1851 was found in an input file.
1852 It is replaced by a question mark.
1853 .It Sy "unsupported roff request"
1854 .Pq roff
1855 An input file contains a
1856 .Xr roff 7
1857 request supported by GNU troff or Heirloom troff but not by
1858 .Nm ,
1859 and it is likely that this will cause information loss
1860 or considerable misformatting.
1861 .It Sy "eqn delim option in tbl"
1862 .Pq eqn , tbl
1863 The options line of a table defines equation delimiters.
1864 Any equation source code contained in the table will be printed unformatted.
1865 .It Sy "unsupported table layout modifier"
1866 .Pq tbl
1867 A table layout specification contains an
1868 .Sq Cm m
1869 modifier.
1870 The modifier is discarded.
1871 .It Sy "ignoring macro in table"
1872 .Pq tbl , mdoc , man
1873 A table contains an invocation of an
1874 .Xr mdoc 7
1875 or
1876 .Xr man 7
1877 macro or of an undefined macro.
1878 The macro is ignored, and its arguments are handled
1879 as if they were a text line.
1880 .El
1881 .Sh SEE ALSO
1882 .Xr apropos 1 ,
1883 .Xr man 1 ,
1884 .Xr eqn 7 ,
1885 .Xr man 7 ,
1886 .Xr mandoc_char 7 ,
1887 .Xr mdoc 7 ,
1888 .Xr roff 7 ,
1889 .Xr tbl 7
1890 .Sh HISTORY
1891 The
1892 .Nm
1893 utility first appeared in
1894 .Ox 4.8 .
1895 The option
1896 .Fl I
1897 appeared in
1898 .Ox 5.2 ,
1899 and
1900 .Fl aCcfhKklMSsw
1901 in
1902 .Ox 5.7 .
1903 .Sh AUTHORS
1904 .An -nosplit
1905 The
1906 .Nm
1907 utility was written by
1908 .An Kristaps Dzonsons Aq Mt kristaps@bsd.lv
1909 and is maintained by
1910 .An Ingo Schwarze Aq Mt schwarze@openbsd.org .