1MAN(1) Manual pager utils MAN(1)
2
3
4
6 man - an interface to the system reference manuals
7
9 man [man options] [[section] page ...] ...
10 man -k [apropos options] regexp ...
11 man -K [man options] [section] term ...
12 man -f [whatis options] page ...
13 man -l [man options] file ...
14 man -w|-W [man options] page ...
15
17 man is the system's manual pager. Each page argument given to man is
18 normally the name of a program, utility or function. The manual page
19 associated with each of these arguments is then found and displayed. A
20 section, if provided, will direct man to look only in that section of
21 the manual. The default action is to search in all of the available
22 sections following a pre-defined order (see DEFAULTS), and to show only
23 the first page found, even if page exists in several sections.
24
25 The table below shows the section numbers of the manual followed by the
26 types of pages they contain.
27
28
29 1 Executable programs or shell commands
30 2 System calls (functions provided by the kernel)
31 3 Library calls (functions within program libraries)
32 4 Special files (usually found in /dev)
33 5 File formats and conventions, e.g. /etc/passwd
34 6 Games
35 7 Miscellaneous (including macro packages and conventions), e.g.
36 man(7), groff(7), man-pages(7)
37 8 System administration commands (usually only for root)
38 9 Kernel routines [Non standard]
39
40 A manual page consists of several sections.
41
42 Conventional section names include NAME, SYNOPSIS, CONFIGURATION, DE‐
43 SCRIPTION, OPTIONS, EXIT STATUS, RETURN VALUE, ERRORS, ENVIRONMENT,
44 FILES, VERSIONS, CONFORMING TO, NOTES, BUGS, EXAMPLE, AUTHORS, and
45 SEE ALSO.
46
47 The following conventions apply to the SYNOPSIS section and can be used
48 as a guide in other sections.
49
50
51 bold text type exactly as shown.
52 italic text replace with appropriate argument.
53 [-abc] any or all arguments within [ ] are optional.
54 -a|-b options delimited by | cannot be used together.
55 argument ... argument is repeatable.
56 [expression] ... entire expression within [ ] is repeatable.
57
58 Exact rendering may vary depending on the output device. For instance,
59 man will usually not be able to render italics when running in a termi‐
60 nal, and will typically use underlined or coloured text instead.
61
62 The command or function illustration is a pattern that should match all
63 possible invocations. In some cases it is advisable to illustrate sev‐
64 eral exclusive invocations as is shown in the SYNOPSIS section of this
65 manual page.
66
68 man ls
69 Display the manual page for the item (program) ls.
70
71 man man.7
72 Display the manual page for macro package man from section 7.
73 (This is an alternative spelling of "man 7 man".)
74
75 man 'man(7)'
76 Display the manual page for macro package man from section 7.
77 (This is another alternative spelling of "man 7 man". It may be
78 more convenient when copying and pasting cross-references to manual
79 pages. Note that the parentheses must normally be quoted to pro‐
80 tect them from the shell.)
81
82 man -a intro
83 Display, in succession, all of the available intro manual pages
84 contained within the manual. It is possible to quit between suc‐
85 cessive displays or skip any of them.
86
87 man -t bash | lpr -Pps
88 Format the manual page for bash into the default troff or groff
89 format and pipe it to the printer named ps. The default output for
90 groff is usually PostScript. man --help should advise as to which
91 processor is bound to the -t option.
92
93 man -l -Tdvi ./foo.1x.gz > ./foo.1x.dvi
94 This command will decompress and format the nroff source manual
95 page ./foo.1x.gz into a device independent (dvi) file. The redi‐
96 rection is necessary as the -T flag causes output to be directed to
97 stdout with no pager. The output could be viewed with a program
98 such as xdvi or further processed into PostScript using a program
99 such as dvips.
100
101 man -k printf
102 Search the short descriptions and manual page names for the keyword
103 printf as regular expression. Print out any matches. Equivalent
104 to apropos printf.
105
106 man -f smail
107 Lookup the manual pages referenced by smail and print out the short
108 descriptions of any found. Equivalent to whatis smail.
109
111 Many options are available to man in order to give as much flexibility
112 as possible to the user. Changes can be made to the search path, sec‐
113 tion order, output processor, and other behaviours and operations de‐
114 tailed below.
115
116 If set, various environment variables are interrogated to determine the
117 operation of man. It is possible to set the "catch-all" variable
118 $MANOPT to any string in command line format, with the exception that
119 any spaces used as part of an option's argument must be escaped (pre‐
120 ceded by a backslash). man will parse $MANOPT prior to parsing its own
121 command line. Those options requiring an argument will be overridden
122 by the same options found on the command line. To reset all of the op‐
123 tions set in $MANOPT, -D can be specified as the initial command line
124 option. This will allow man to "forget" about the options specified in
125 $MANOPT, although they must still have been valid.
126
127 Manual pages are normally stored in nroff(1) format under a directory
128 such as /usr/share/man. In some installations, there may also be pre‐
129 formatted cat pages to improve performance. See manpath(5) for details
130 of where these files are stored.
131
132 This package supports manual pages in multiple languages, controlled by
133 your locale. If your system did not set this up for you automatically,
134 then you may need to set $LC_MESSAGES, $LANG, or another system-depen‐
135 dent environment variable to indicate your preferred locale, usually
136 specified in the POSIX format:
137
138 <language>[_<territory>[.<character-set>[,<version>]]]
139
140 If the desired page is available in your locale, it will be displayed
141 in lieu of the standard (usually American English) page.
142
143 If you find that the translations supplied with this package are not
144 available in your native language and you would like to supply them,
145 please contact the maintainer who will be coordinating such activity.
146
147 Individual manual pages are normally written and maintained by the
148 maintainers of the program, function, or other topic that they docu‐
149 ment, and are not included with this package. If you find that a man‐
150 ual page is missing or inadequate, please report that to the maintain‐
151 ers of the package in question.
152
153 For information regarding other features and extensions available with
154 this manual pager, please read the documents supplied with the package.
155
157 The order of sections to search may be overridden by the environment
158 variable $MANSECT or by the SECTION directive in /etc/man_db.conf. By
159 default it is as follows:
160
161 1 1p 8 2 3 3p 3pm 4 5 6 7 9 0p n l p o 1x 2x 3x 4x 5x 6x 7x 8x
162
163 The formatted manual page is displayed using a pager. This can be
164 specified in a number of ways, or else will fall back to a default (see
165 option -P for details).
166
167 The filters are deciphered by a number of means. Firstly, the command
168 line option -p or the environment variable $MANROFFSEQ is interrogated.
169 If -p was not used and the environment variable was not set, the ini‐
170 tial line of the nroff file is parsed for a preprocessor string. To
171 contain a valid preprocessor string, the first line must resemble
172
173 '\" <string>
174
175 where string can be any combination of letters described by option -p
176 below.
177
178 If none of the above methods provide any filter information, a default
179 set is used.
180
181 A formatting pipeline is formed from the filters and the primary for‐
182 matter (nroff or [tg]roff with -t) and executed. Alternatively, if an
183 executable program mandb_nfmt (or mandb_tfmt with -t) exists in the man
184 tree root, it is executed instead. It gets passed the manual source
185 file, the preprocessor string, and optionally the device specified with
186 -T or -E as arguments.
187
189 Non-argument options that are duplicated either on the command line, in
190 $MANOPT, or both, are not harmful. For options that require an argu‐
191 ment, each duplication will override the previous argument value.
192
193 General options
194 -C file, --config-file=file
195 Use this user configuration file rather than the default of
196 ~/.manpath.
197
198 -d, --debug
199 Print debugging information.
200
201 -D, --default
202 This option is normally issued as the very first option and re‐
203 sets man's behaviour to its default. Its use is to reset those
204 options that may have been set in $MANOPT. Any options that
205 follow -D will have their usual effect.
206
207 --warnings[=warnings]
208 Enable warnings from groff. This may be used to perform sanity
209 checks on the source text of manual pages. warnings is a comma-
210 separated list of warning names; if it is not supplied, the de‐
211 fault is "mac". See the “Warnings” node in info groff for a
212 list of available warning names.
213
214 Main modes of operation
215 -f, --whatis
216 Equivalent to whatis. Display a short description from the man‐
217 ual page, if available. See whatis(1) for details.
218
219 -k, --apropos
220 Equivalent to apropos. Search the short manual page descrip‐
221 tions for keywords and display any matches. See apropos(1) for
222 details.
223
224 -K, --global-apropos
225 Search for text in all manual pages. This is a brute-force
226 search, and is likely to take some time; if you can, you should
227 specify a section to reduce the number of pages that need to be
228 searched. Search terms may be simple strings (the default), or
229 regular expressions if the --regex option is used.
230
231 Note that this searches the sources of the manual pages, not the
232 rendered text, and so may include false positives due to things
233 like comments in source files. Searching the rendered text
234 would be much slower.
235
236 -l, --local-file
237 Activate "local" mode. Format and display local manual files
238 instead of searching through the system's manual collection.
239 Each manual page argument will be interpreted as an nroff source
240 file in the correct format. No cat file is produced. If '-' is
241 listed as one of the arguments, input will be taken from stdin.
242 When this option is not used, and man fails to find the page re‐
243 quired, before displaying the error message, it attempts to act
244 as if this option was supplied, using the name as a filename and
245 looking for an exact match.
246
247 -w, --where, --path, --location
248 Don't actually display the manual page, but do print the loca‐
249 tion of the source nroff file that would be formatted. If the
250 -a option is also used, then print the locations of all source
251 files that match the search criteria.
252
253 -W, --where-cat, --location-cat
254 Don't actually display the manual page, but do print the loca‐
255 tion of the preformatted cat file that would be displayed. If
256 the -a option is also used, then print the locations of all pre‐
257 formatted cat files that match the search criteria.
258
259 If -w and -W are both used, then print both source file and cat
260 file separated by a space. If all of -w, -W, and -a are used,
261 then do this for each possible match.
262
263 -c, --catman
264 This option is not for general use and should only be used by
265 the catman program.
266
267 -R encoding, --recode=encoding
268 Instead of formatting the manual page in the usual way, output
269 its source converted to the specified encoding. If you already
270 know the encoding of the source file, you can also use man‐
271 conv(1) directly. However, this option allows you to convert
272 several manual pages to a single encoding without having to ex‐
273 plicitly state the encoding of each, provided that they were al‐
274 ready installed in a structure similar to a manual page hierar‐
275 chy.
276
277 Consider using man-recode(1) instead for converting multiple
278 manual pages, since it has an interface designed for bulk con‐
279 version and so can be much faster.
280
281 Finding manual pages
282 -L locale, --locale=locale
283 man will normally determine your current locale by a call to the
284 C function setlocale(3) which interrogates various environment
285 variables, possibly including $LC_MESSAGES and $LANG. To tempo‐
286 rarily override the determined value, use this option to supply
287 a locale string directly to man. Note that it will not take ef‐
288 fect until the search for pages actually begins. Output such as
289 the help message will always be displayed in the initially de‐
290 termined locale.
291
292 -m system[,...], --systems=system[,...]
293 If this system has access to other operating systems' manual
294 pages, they can be accessed using this option. To search for a
295 manual page from NewOS's manual page collection, use the option
296 -m NewOS.
297
298 The system specified can be a combination of comma delimited op‐
299 erating system names. To include a search of the native operat‐
300 ing system's manual pages, include the system name man in the
301 argument string. This option will override the $SYSTEM environ‐
302 ment variable.
303
304 -M path, --manpath=path
305 Specify an alternate manpath to use. By default, man uses man‐
306 path derived code to determine the path to search. This option
307 overrides the $MANPATH environment variable and causes option -m
308 to be ignored.
309
310 A path specified as a manpath must be the root of a manual page
311 hierarchy structured into sections as described in the man-db
312 manual (under "The manual page system"). To view manual pages
313 outside such hierarchies, see the -l option.
314
315 -S list, -s list, --sections=list
316 The given list is a colon- or comma-separated list of sections,
317 used to determine which manual sections to search and in what
318 order. This option overrides the $MANSECT environment variable.
319 (The -s spelling is for compatibility with System V.)
320
321 -e sub-extension, --extension=sub-extension
322 Some systems incorporate large packages of manual pages, such as
323 those that accompany the Tcl package, into the main manual page
324 hierarchy. To get around the problem of having two manual pages
325 with the same name such as exit(3), the Tcl pages were usually
326 all assigned to section l. As this is unfortunate, it is now
327 possible to put the pages in the correct section, and to assign
328 a specific "extension" to them, in this case, exit(3tcl). Under
329 normal operation, man will display exit(3) in preference to
330 exit(3tcl). To negotiate this situation and to avoid having to
331 know which section the page you require resides in, it is now
332 possible to give man a sub-extension string indicating which
333 package the page must belong to. Using the above example, sup‐
334 plying the option -e tcl to man will restrict the search to
335 pages having an extension of *tcl.
336
337 -i, --ignore-case
338 Ignore case when searching for manual pages. This is the de‐
339 fault.
340
341 -I, --match-case
342 Search for manual pages case-sensitively.
343
344 --regex
345 Show all pages with any part of either their names or their de‐
346 scriptions matching each page argument as a regular expression,
347 as with apropos(1). Since there is usually no reasonable way to
348 pick a "best" page when searching for a regular expression, this
349 option implies -a.
350
351 --wildcard
352 Show all pages with any part of either their names or their de‐
353 scriptions matching each page argument using shell-style wild‐
354 cards, as with apropos(1) --wildcard. The page argument must
355 match the entire name or description, or match on word bound‐
356 aries in the description. Since there is usually no reasonable
357 way to pick a "best" page when searching for a wildcard, this
358 option implies -a.
359
360 --names-only
361 If the --regex or --wildcard option is used, match only page
362 names, not page descriptions, as with whatis(1). Otherwise, no
363 effect.
364
365 -a, --all
366 By default, man will exit after displaying the most suitable
367 manual page it finds. Using this option forces man to display
368 all the manual pages with names that match the search criteria.
369
370 -u, --update
371 This option causes man to update its database caches of in‐
372 stalled manual pages. This is only needed in rare situations,
373 and it is normally better to run mandb(8) instead.
374
375 --no-subpages
376 By default, man will try to interpret pairs of manual page names
377 given on the command line as equivalent to a single manual page
378 name containing a hyphen or an underscore. This supports the
379 common pattern of programs that implement a number of subcom‐
380 mands, allowing them to provide manual pages for each that can
381 be accessed using similar syntax as would be used to invoke the
382 subcommands themselves. For example:
383
384 $ man -aw git diff
385 /usr/share/man/man1/git-diff.1.gz
386
387 To disable this behaviour, use the --no-subpages option.
388
389 $ man -aw --no-subpages git diff
390 /usr/share/man/man1/git.1.gz
391 /usr/share/man/man3/Git.3pm.gz
392 /usr/share/man/man1/diff.1.gz
393
394 Controlling formatted output
395 -P pager, --pager=pager
396 Specify which output pager to use. By default, man uses less,
397 falling back to cat if less is not found or is not executable.
398 This option overrides the $MANPAGER environment variable, which
399 in turn overrides the $PAGER environment variable. It is not
400 used in conjunction with -f or -k.
401
402 The value may be a simple command name or a command with argu‐
403 ments, and may use shell quoting (backslashes, single quotes, or
404 double quotes). It may not use pipes to connect multiple com‐
405 mands; if you need that, use a wrapper script, which may take
406 the file to display either as an argument or on standard input.
407
408 -r prompt, --prompt=prompt
409 If a recent version of less is used as the pager, man will at‐
410 tempt to set its prompt and some sensible options. The default
411 prompt looks like
412
413 Manual page name(sec) line x
414
415 where name denotes the manual page name, sec denotes the section
416 it was found under and x the current line number. This is
417 achieved by using the $LESS environment variable.
418
419 Supplying -r with a string will override this default. The
420 string may contain the text $MAN_PN which will be expanded to
421 the name of the current manual page and its section name sur‐
422 rounded by "(" and ")". The string used to produce the default
423 could be expressed as
424
425 \ Manual\ page\ \$MAN_PN\ ?ltline\ %lt?L/%L.:
426 byte\ %bB?s/%s..?\ (END):?pB\ %pB\\%..
427 (press h for help or q to quit)
428
429 It is broken into three lines here for the sake of readability
430 only. For its meaning see the less(1) manual page. The prompt
431 string is first evaluated by the shell. All double quotes,
432 back-quotes and backslashes in the prompt must be escaped by a
433 preceding backslash. The prompt string may end in an escaped $
434 which may be followed by further options for less. By default
435 man sets the -ix8 options.
436
437 The $MANLESS environment variable described below may be used to
438 set a default prompt string if none is supplied on the command
439 line.
440
441 -7, --ascii
442 When viewing a pure ascii(7) manual page on a 7 bit terminal or
443 terminal emulator, some characters may not display correctly
444 when using the latin1(7) device description with GNU nroff.
445 This option allows pure ascii manual pages to be displayed in
446 ascii with the latin1 device. It will not translate any latin1
447 text. The following table shows the translations performed:
448 some parts of it may only be displayed properly when using GNU
449 nroff's latin1(7) device.
450
451
452 Description Octal latin1 ascii
453 ──────────────────────────────────────────
454 continuation hy‐ 255 ‐ -
455 phen
456 bullet (middle 267 • o
457 dot)
458 acute accent 264 ´ '
459 multiplication 327 × x
460 sign
461
462 If the latin1 column displays correctly, your terminal may be
463 set up for latin1 characters and this option is not necessary.
464 If the latin1 and ascii columns are identical, you are reading
465 this page using this option or man did not format this page us‐
466 ing the latin1 device description. If the latin1 column is
467 missing or corrupt, you may need to view manual pages with this
468 option.
469
470 This option is ignored when using options -t, -H, -T, or -Z and
471 may be useless for nroff other than GNU's.
472
473 -E encoding, --encoding=encoding
474 Generate output for a character encoding other than the default.
475 For backward compatibility, encoding may be an nroff device such
476 as ascii, latin1, or utf8 as well as a true character encoding
477 such as UTF-8.
478
479 --no-hyphenation, --nh
480 Normally, nroff will automatically hyphenate text at line breaks
481 even in words that do not contain hyphens, if it is necessary to
482 do so to lay out words on a line without excessive spacing.
483 This option disables automatic hyphenation, so words will only
484 be hyphenated if they already contain hyphens.
485
486 If you are writing a manual page and simply want to prevent
487 nroff from hyphenating a word at an inappropriate point, do not
488 use this option, but consult the nroff documentation instead;
489 for instance, you can put "\%" inside a word to indicate that it
490 may be hyphenated at that point, or put "\%" at the start of a
491 word to prevent it from being hyphenated.
492
493 --no-justification, --nj
494 Normally, nroff will automatically justify text to both margins.
495 This option disables full justification, leaving justified only
496 to the left margin, sometimes called "ragged-right" text.
497
498 If you are writing a manual page and simply want to prevent
499 nroff from justifying certain paragraphs, do not use this op‐
500 tion, but consult the nroff documentation instead; for instance,
501 you can use the ".na", ".nf", ".fi", and ".ad" requests to tem‐
502 porarily disable adjusting and filling.
503
504 -p string, --preprocessor=string
505 Specify the sequence of preprocessors to run before nroff or
506 troff/groff. Not all installations will have a full set of pre‐
507 processors. Some of the preprocessors and the letters used to
508 designate them are: eqn (e), grap (g), pic (p), tbl (t), vgrind
509 (v), refer (r). This option overrides the $MANROFFSEQ environ‐
510 ment variable. zsoelim is always run as the very first pre‐
511 processor.
512
513 -t, --troff
514 Use groff -mandoc to format the manual page to stdout. This op‐
515 tion is not required in conjunction with -H, -T, or -Z.
516
517 -T[device], --troff-device[=device]
518 This option is used to change groff (or possibly troff's) output
519 to be suitable for a device other than the default. It implies
520 -t. Examples (provided with Groff-1.17) include dvi, latin1,
521 ps, utf8, X75 and X100.
522
523 -H[browser], --html[=browser]
524 This option will cause groff to produce HTML output, and will
525 display that output in a web browser. The choice of browser is
526 determined by the optional browser argument if one is provided,
527 by the $BROWSER environment variable, or by a compile-time de‐
528 fault if that is unset (usually lynx). This option implies -t,
529 and will only work with GNU troff.
530
531 -X[dpi], --gxditview[=dpi]
532 This option displays the output of groff in a graphical window
533 using the gxditview program. The dpi (dots per inch) may be 75,
534 75-12, 100, or 100-12, defaulting to 75; the -12 variants use a
535 12-point base font. This option implies -T with the X75,
536 X75-12, X100, or X100-12 device respectively.
537
538 -Z, --ditroff
539 groff will run troff and then use an appropriate post-processor
540 to produce output suitable for the chosen device. If groff
541 -mandoc is groff, this option is passed to groff and will sup‐
542 press the use of a post-processor. It implies -t.
543
544 Getting help
545 -?, --help
546 Print a help message and exit.
547
548 --usage
549 Print a short usage message and exit.
550
551 -V, --version
552 Display version information.
553
555 0 Successful program execution.
556
557 1 Usage, syntax or configuration file error.
558
559 2 Operational error.
560
561 3 A child process returned a non-zero exit status.
562
563 16 At least one of the pages/files/keywords didn't exist or wasn't
564 matched.
565
567 MANPATH
568 If $MANPATH is set, its value is used as the path to search for
569 manual pages.
570
571 See the SEARCH PATH section of manpath(5) for the default behav‐
572 iour and details of how this environment variable is handled.
573
574 MANROFFOPT
575 Every time man invokes the formatter (nroff, troff, or groff),
576 it adds the contents of $MANROFFOPT to the formatter's command
577 line.
578
579 MANROFFSEQ
580 If $MANROFFSEQ is set, its value is used to determine the set of
581 preprocessors to pass each manual page through. The default
582 preprocessor list is system dependent.
583
584 MANSECT
585 If $MANSECT is set, its value is a colon-delimited list of sec‐
586 tions and it is used to determine which manual sections to
587 search and in what order. The default is "1 1p 8 2 3 3p 3pm 4 5
588 6 7 9 0p n l p o 1x 2x 3x 4x 5x 6x 7x 8x", unless overridden by
589 the SECTION directive in /etc/man_db.conf.
590
591 MANPAGER, PAGER
592 If $MANPAGER or $PAGER is set ($MANPAGER is used in preference),
593 its value is used as the name of the program used to display the
594 manual page. By default, less is used, falling back to cat if
595 less is not found or is not executable.
596
597 The value may be a simple command name or a command with argu‐
598 ments, and may use shell quoting (backslashes, single quotes, or
599 double quotes). It may not use pipes to connect multiple com‐
600 mands; if you need that, use a wrapper script, which may take
601 the file to display either as an argument or on standard input.
602
603 MANLESS
604 If $MANLESS is set, its value will be used as the default prompt
605 string for the less pager, as if it had been passed using the -r
606 option (so any occurrences of the text $MAN_PN will be expanded
607 in the same way). For example, if you want to set the prompt
608 string unconditionally to “my prompt string”, set $MANLESS to
609 ‘-Psmy prompt string’. Using the -r option overrides this envi‐
610 ronment variable.
611
612 BROWSER
613 If $BROWSER is set, its value is a colon-delimited list of com‐
614 mands, each of which in turn is used to try to start a web
615 browser for man --html. In each command, %s is replaced by a
616 filename containing the HTML output from groff, %% is replaced
617 by a single percent sign (%), and %c is replaced by a colon (:).
618
619 SYSTEM If $SYSTEM is set, it will have the same effect as if it had
620 been specified as the argument to the -m option.
621
622 MANOPT If $MANOPT is set, it will be parsed prior to man's command line
623 and is expected to be in a similar format. As all of the other
624 man specific environment variables can be expressed as command
625 line options, and are thus candidates for being included in
626 $MANOPT it is expected that they will become obsolete. N.B.
627 All spaces that should be interpreted as part of an option's ar‐
628 gument must be escaped.
629
630 MANWIDTH
631 If $MANWIDTH is set, its value is used as the line length for
632 which manual pages should be formatted. If it is not set, man‐
633 ual pages will be formatted with a line length appropriate to
634 the current terminal (using the value of $COLUMNS, and ioctl(2)
635 if available, or falling back to 80 characters if neither is
636 available). Cat pages will only be saved when the default for‐
637 matting can be used, that is when the terminal line length is
638 between 66 and 80 characters.
639
640 MAN_KEEP_FORMATTING
641 Normally, when output is not being directed to a terminal (such
642 as to a file or a pipe), formatting characters are discarded to
643 make it easier to read the result without special tools. How‐
644 ever, if $MAN_KEEP_FORMATTING is set to any non-empty value,
645 these formatting characters are retained. This may be useful
646 for wrappers around man that can interpret formatting charac‐
647 ters.
648
649 MAN_KEEP_STDERR
650 Normally, when output is being directed to a terminal (usually
651 to a pager), any error output from the command used to produce
652 formatted versions of manual pages is discarded to avoid inter‐
653 fering with the pager's display. Programs such as groff often
654 produce relatively minor error messages about typographical
655 problems such as poor alignment, which are unsightly and gener‐
656 ally confusing when displayed along with the manual page. How‐
657 ever, some users want to see them anyway, so, if
658 $MAN_KEEP_STDERR is set to any non-empty value, error output
659 will be displayed as usual.
660
661 MAN_DISABLE_SECCOMP
662 On Linux, man normally confines subprocesses that handle un‐
663 trusted data using a seccomp(2) sandbox. This makes it safer to
664 run complex parsing code over arbitrary manual pages. If this
665 goes wrong for some reason unrelated to the content of the page
666 being displayed, you can set $MAN_DISABLE_SECCOMP to any non-
667 empty value to disable the sandbox.
668
669 PIPELINE_DEBUG
670 If the $PIPELINE_DEBUG environment variable is set to "1", then
671 man will print debugging messages to standard error describing
672 each subprocess it runs.
673
674 LANG, LC_MESSAGES
675 Depending on system and implementation, either or both of $LANG
676 and $LC_MESSAGES will be interrogated for the current message
677 locale. man will display its messages in that locale (if avail‐
678 able). See setlocale(3) for precise details.
679
681 /etc/man_db.conf
682 man-db configuration file.
683
684 /usr/share/man
685 A global manual page hierarchy.
686
688 apropos(1), groff(1), less(1), manpath(1), nroff(1), troff(1),
689 whatis(1), zsoelim(1), manpath(5), man(7), catman(8), mandb(8)
690
691 Documentation for some packages may be available in other formats, such
692 as info(1) or HTML.
693
695 1990, 1991 – Originally written by John W. Eaton (jwe@che.utexas.edu).
696
697 Dec 23 1992: Rik Faith (faith@cs.unc.edu) applied bug fixes supplied by
698 Willem Kasdorp (wkasdo@nikhefk.nikef.nl).
699
700 30th April 1994 – 23rd February 2000: Wilf. (G.Wilford@ee.surrey.ac.uk)
701 has been developing and maintaining this package with the help of a few
702 dedicated people.
703
704 30th October 1996 – 30th March 2001: Fabrizio Polacco <fpolacco@de‐
705 bian.org> maintained and enhanced this package for the Debian project,
706 with the help of all the community.
707
708 31st March 2001 – present day: Colin Watson <cjwatson@debian.org> is
709 now developing and maintaining man-db.
710
712 https://gitlab.com/man-db/man-db/-/issues
713 https://savannah.nongnu.org/bugs/?group=man-db
714
715
716
7172.11.2 2023-01-08 MAN(1)