1Locale::Po4a::Man(3pm) Po4a Tools Locale::Po4a::Man(3pm)
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6 Locale::Po4a::Man - convert manual pages from/to PO files
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9 The po4a (PO for anything) project goal is to ease translations (and
10 more interestingly, the maintenance of translations) using gettext
11 tools on areas where they were not expected like documentation.
12 Locale::Po4a::Man is a module to help the translation of documentation
14 in the nroff format (the language of manual pages) into other [human]
15 languages.
16
18 This module tries pretty hard to make translator's life easier. For
19 that, the text presented to translators isn't a verbatim copy of the
20 text found in the man page. Indeed, the cruder parts of the nroff
21 format are hidden, so that translators can't mess up with them.
22 Text wrapping
24 Unindented paragraphs are automatically rewrapped for the translator.
25 This can lead to some minor difference in the generated output, since
26 the rewrapping rules used by groff aren't very clear. For example, two
27 spaces after a parenthesis are sometimes preserved.
28 Anyway, the difference will only be about the position of the extra
30 spaces in wrapped paragraph, and I think it's worth.
31 Font specification
33 The first change is about font change specifications. In nroff, there
34 are several ways to specify if a given word should be written in small,
35 bold or italics. In the text to translate, there is only one way,
36 borrowed from the POD (Perl online documentation) format:
37 I<text> -- italic text
39 equivalent to \fItext\fP or ".I text"
40 B<text> -- bold text
42 equivalent to \fBtext\fP or ".B text"
43 R<text> -- roman text
45 equivalent to \fRtext\fP
46 CW<text> -- constant width text
48 equivalent to \f(CWtext\fP or ".CW text"
49 Remark: The CW face is not available for all groff devices. It is not
51 recommended to use it. It is provided for your convenience.
52 Automatic characters transliteration
54 Po4a automatically transliterate some characters to ease the
55 translation or the review of the translation. Here is the list of the
56 transliterations:
57 hyphens
59 Hyphens (-) and minus signs (\-) in man pages are all
60 transliterated as simple dashes (-) in the PO file. Then all dash
61 are transliterated into roff minus signs (\-) when the translation
62 is inserted into the output document.
63 Translators can force an hyphen by using the roff glyph '\[hy]' in
65 their translations.
66 non-breaking spaces
68 Translators can use non-breaking spaces in their translations.
69 These non-breaking spaces (0xA0 in latin1) will be transliterated
70 into a roff non-breaking space ('\ ').
71 quotes transliterations
73 `` and '' are respectively tranliterated into \*(lq and \*(rq.
74 To avoid these transliterations, translators can insert a zero
76 width roff character (i.e., using `\&` or '\&' respectively).
77 Putting '<' and '>' in translations
79 Since these chars are used to delimit parts under font modification,
80 you can't use them verbatim. Use E<lt> and E<gt> instead (as in POD,
81 one more time).
82
84 These are this module's particular options:
85 debug
87 Activate debugging for some internal mechanisms of this module.
88 Use the source to see which parts can be debugged.
89 verbose
91 Increase verbosity.
92 groff_code
94 This option permits to change the behavior of the module when it
95 encounter a .de, .ie or .if section. It can take the following
96 values:
97 fail
99 This is the default value. The module will fail when a .de,
100 .ie or .if section is encountered.
101 verbatim
103 Indicates that the .de, .ie or .if sections must be copied as
104 is from the original to the translated document.
105 translate
107 Indicates that the .de, .ie or .if sections will be proposed
108 for the translation. You should only use this option if a
109 translatable string is contained in one of these section.
110 Otherwise, verbatim should be preferred.
111 generated
113 This option specifies that the file was generated, and that po4a
114 should not try to detect if the man pages was generated from
115 another format. This permits to use po4a on generated man pages.
116 This option does not take any argument.
117 mdoc
119 This option is only useful for mdoc pages.
120 It selects a stricter support of the mdoc format by telling po4a
122 not to translate the 'NAME' section. mdoc pages whose 'NAME'
123 section is translated won't generate any header or footer.
124 According to the groff_mdoc page, the NAME, SYNOPSIS and
126 DESCRIPTION sections are mandatory. There are no known issues with
127 translated SYNOPSIS or DESCRIPTION section, but you can also
128 specify these sections this way:
129 -o mdoc=NAME,SYNOPSIS,DESCRIPTION
130 This mdoc issue can also be solved with an addendum like this one:
132 PO4A-HEADER:mode=before;position=^.Dd
133 .TH DOCUMENT_TITLE 1 "Month day, year" OS "Section Name"
134 The following options permit to specify the behavior of a new macro
136 (defined with a .de request), or of a macro not supported by po4a.
137 They take as argument a comma-separated list of macros. For example:
138 -o noarg=FO,OB,AR -o translate_joined=BA,ZQ,UX
140 Note: if a macro is not supported by po4a and if you consider that it
142 is a standard roff macro, you should submit it to the po4a development
143 team.
144 untranslated
146 untranslated indicates that this macro (at its arguments) don't
147 have to be translated.
148 noarg
150 noarg is like untranslated, except that po4a will verify that no
151 argument is added to this macro.
152 translate_joined
154 translate_joined indicates that po4a must propose to translate the
155 arguments of the macro.
156 translate_each
158 With translate_each, the arguments will also be proposed for the
159 translation, except that each one will be translated separately.
160 no_wrap
162 This option takes as argument a list of comma-separated couples
163 begin:end, where begin and end are commands that delimit the begin
164 and end of a section that should not be rewrapped.
165 Note: no test is done to ensure that an end command matches its
167 begin command; any ending command stop the no_wrap mode. If you
168 have a begin (respectively end) macro that has no end (respectively
169 begin), you can specify an existing end (like fi) or begin (like
170 nf) as a counterpart. These macros (and their arguments) wont be
171 translated.
172 inline
174 This option specifies a list of comma-separated macros that must
175 not split the current paragraph. The string to translate will then
176 contain foo <.bar baz qux> quux, where bar is the command that
177 should be inlined, and baz qux its arguments.
178 unknown_macros
180 This option indicates how po4a should behave when an unknown macro
181 is found. By default, po4a fails with a warning. It can take the
182 following values: failed (the default value), untranslated, noarg,
183 translate_joined, or translate_each (see above for an explanation
184 of these values).
185
187 This module is still very limited, and will always be, because it's not
188 a real nroff interpreter. It would be possible to do a real nroff
189 interpreter, to allow authors to use all the existing macros, or even
190 to define new ones in their pages, but we didn't want to. It would be
191 too difficult, and we thought it wasn't necessary. We do think that if
192 manpages' authors want to see their productions translated, they may
193 have to adapt to ease the work of translators.
194 So, the man parser implemented in po4a have some known limitations we
196 are not really inclined to correct, and which will constitute some
197 pitfalls you'll have to avoid if you want to see translators taking
198 care of your documentation.
199 Don't program in nroff
201 nroff is a complete programming language, with macro definition,
202 conditionals and so on. Since this parser isn't a fully featured nroff
203 interpreter, it will fail on pages using these facilities (There are
204 about 200 such pages on my box).
205 Use the plain macro set
207 There are still some macros which are not supported by po4a::man. This
208 is only because I failed to find any documentation about them. Here is
209 the list of unsupported macros used on my box. Note that this list
210 isn't exhaustive since the program fails on the first encountered
211 unsupported macro. If you have any information about some of these
212 macros, I'll happily add support for them. Because of these macros,
213 about 250 pages on my box are inaccessible to po4a::man.
214 .. ." .AT .b .bank
216 .BE ..br .Bu .BUGS .BY
217 .ce .dbmmanage .do .En
218 .EP .EX .Fi .hw .i
219 .Id .l .LO .mf
220 .N .na .NF .nh .nl
221 .Nm .ns .NXR .OPTIONS .PB
222 .pp .PR .PRE .PU .REq
223 .RH .rn .S< .sh .SI
224 .splitfont .Sx .T .TF .The
225 .TT .UC .ul .Vb .zZ
226 Hiding text from po4a
228 Sometimes, the author knows that some parts are not translatable, and
229 should not be extracted by po4a. For example, an option may accept an
230 other argument, and other may also appear as the last item of a list.
231 In the first case, other should be not be translatable. And in the
232 second case, other should be translated.
233 In such case, the author can avoid po4a to extract some strings, using
235 some special groff constructs:
236 .if !'po4a'hide' .B other
238 (this will require the -o groff_code=verbatim option)
240 A new macro can also be defined to automate this:
242 .de IR_untranslated
243 . IR \\$@
244 ..
245 .IR_untranslated \-q ", " \-\-quiet
247 (this will require the options -o groff_code=verbatim and -o
249 untranslated=IR_untranslated; with this construct, the .if !'po4a'hide'
250 conditional is not strictly needed since po4a will not parse the
251 internal of the macro definition)
252 or using an alias:
254 .als IR_untranslated IR
255 .IR_untranslated \-q ", " \-\-quiet
257 This will require the -o untranslated=als,IR_untranslated option.
259 Conclusion
261 To summarise this section, keep simple, and don't try to be clever
262 while authoring your man pages. A lot of things are possible in nroff,
263 and not supported by this parser. For example, don't try to mess with
264 \c to interrupt the text processing (like 40 pages on my box do). Or,
265 be sure to put the macro arguments on the same line that the macro
266 itself. I know that it's valid in nroff, but would complicate too much
267 the parser to be handled.
268 Of course, another possibility is to use another format, more
270 translator friendly (like POD using po4a::pod, or one of the XML family
271 like SGML), but thanks to po4a::man it isn't needed anymore. That being
272 said, if the source format of your documentation is POD, or XML, it may
273 be clever to translate the source format and not this generated one. In
274 most cases, po4a::man will detect generated pages and issue a warning.
275 It will even refuse to process POD generated pages, because those pages
276 are perfectly handled by po4a::pod, and because their nroff counterpart
277 defines a lot of new macros I didn't want to write support for. On my
278 box, 1432 of the 4323 pages are generated from POD and will be ignored
279 by po4a::man.
280 In most cases, po4a::man will detect the problem and refuse to process
282 the page, issuing an adapted message. In some rare cases, the program
283 will complete without warning, but the output will be wrong. Such cases
284 are called "bugs" ;) If you encounter such case, be sure to report
285 this, along with a fix when possible…
286
288 This module can be used for most of the existing man pages.
289 Some tests are regularly run on Linux boxes:
291 · one third of the pages are refused because they were generated from
293 another format supported by po4a (e.g. POD or SGML).
294 · 10% of the remaining pages are rejected with an error (e.g. a groff
296 macro is not supported).
297 · Then, less than 1% of the pages are accepted silently by po4a, but
299 with significant issues (i.e. missing words, or new words inserted)
300 · The other pages are usually handled without differences more
302 important than spacing differences or line rewrapped (font issues
303 in less than 10% of the processed pages).
304
306 Locale::Po4a::Pod(3pm), Locale::Po4a::TransTractor(3pm), po4a(7)
307
309 Denis Barbier <barbier@linuxfr.org>
310 Nicolas François <nicolas.francois@centraliens.net>
311 Martin Quinson (mquinson#debian.org)
312
314 Copyright © 2002-2008 SPI, Inc.
315 This program is free software; you may redistribute it and/or modify it
317 under the terms of GPL (see the COPYING file).
318Po4a Tools 2020-01-30 Locale::Po4a::Man(3pm)