faq.doc 10.8 KB
Newer Older
1 2
/******************************************************************************
 *
3
 * 
4
 *
Dimitri van Heesch's avatar
Dimitri van Heesch committed
5
 * Copyright (C) 1997-2013 by Dimitri van Heesch.
6 7 8 9 10 11 12
 *
 * Permission to use, copy, modify, and distribute this software and its
 * documentation under the terms of the GNU General Public License is hereby 
 * granted. No representations are made about the suitability of this software 
 * for any purpose. It is provided "as is" without express or implied warranty.
 * See the GNU General Public License for more details.
 *
Dimitri van Heesch's avatar
Dimitri van Heesch committed
13 14
 * Documents produced by Doxygen are derivative works derived from the
 * input used in their production; they are not affected by this license.
15 16 17 18 19
 *
 */
/*! \page faq Frequently Asked Questions

<ol>
20
<li><b>How to get information on the index page in HTML?</b>
21
<p>
22
You should use the \ref cmdmainpage "\\mainpage" command inside a comment block like this:
23
\verbatim
24
/*! \mainpage My Personal Index Page
25
 *
26
 * \section intro_sec Introduction
27 28 29
 *
 * This is the introduction.
 *
30
 * \section install_sec Installation
31 32 33 34
 *
 * \subsection step1 Step 1: Opening the box
 *  
 * etc...
35 36 37
 */
\endverbatim

38 39 40 41 42 43
<li><b>Help, some/all of the members of my class / file / namespace 
       are not documented?</b>

  Check the following:
  <ol>
  <li>Is your class / file / namespace documented? If not, it will not 
44
      be extracted from the sources unless \ref cfg_extract_all "EXTRACT_ALL" is set to \c YES
45
      in the config file.
46
  <li>Are the members private? If so, you must set \ref cfg_extract_private "EXTRACT_PRIVATE" to \c YES
47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64
      to make them appear in the documentation.
  <li>Is there a function macro in your class that does not end with a 
      semicolon (e.g. MY_MACRO())? If so then you have to instruct 
      doxygen's preprocessor to remove it.

      This typically boils down to the following settings in the config file:

      \verbatim
ENABLE_PREPROCESSING   = YES
MACRO_EXPANSION        = YES
EXPAND_ONLY_PREDEF     = YES
PREDEFINED             = MY_MACRO()=
      \endverbatim

      Please read the \ref preprocessing "preprocessing" section of the
      manual for more information.
  </ol> 

65
<li><b>When I set EXTRACT_ALL to NO none of my functions are shown in the 
66
    documentation.</b>
67 68 69

In order for global functions, variables, enums, typedefs, and defines 
to be documented you should document the file in which these commands are
70
located using a comment block containing a \ref cmdfile "\\file" (or \ref cmdfile "\@file") 
71 72 73
command. 

Alternatively, you can put all members in a group (or module)
74 75
using the \ref cmdingroup "\\ingroup" command and then document the group using a comment
block containing the \ref cmddefgroup "\\defgroup" command.
76 77 78

For member functions or functions that are part of a namespace you should
document either the class or namespace.
79
 
80
<li><b>How can I make doxygen ignore some code fragment?</b>
81 82

The new and easiest way is to add one comment block 
Dimitri van Heesch's avatar
Dimitri van Heesch committed
83
with a \ref cmdcond "\\cond" command at the start and one comment block 
84 85 86 87
with a \ref cmdendcond "\\endcond" command at the end of the piece of
code that should be ignored. This should be within the same file of course.

But you can also use Doxygen's preprocessor for this: 
88 89 90 91 92 93 94 95 96 97 98 99 100
If you put
\verbatim
#ifndef DOXYGEN_SHOULD_SKIP_THIS

 /* code that must be skipped by Doxygen */

#endif /* DOXYGEN_SHOULD_SKIP_THIS */
\endverbatim
around the blocks that should be hidden and put:
\verbatim
  PREDEFINED = DOXYGEN_SHOULD_SKIP_THIS
\endverbatim
in the config file then all blocks should be skipped by Doxygen as long
101
as \ref cfg_enable_preprocessing "ENABLE_PREPROCESSING" is set to `YES`.
102

103 104
<li><b>How can I change what is after the <code>\#include</code> 
in the class documentation?</b>
105

106 107
In most cases you can use \ref cfg_strip_from_inc_path "STRIP_FROM_INC_PATH" 
to strip a user defined part of a path.
108 109

You can also document your class as follows
110 111 112 113 114 115 116 117 118 119

\verbatim
/*! \class MyClassName include.h path/include.h
 *
 *  Docs for MyClassName
 */
\endverbatim

To make doxygen put <br><br>
<code>
120
\#include \<path/include.h\>
121 122 123 124 125
</code>

in the documentation of the class MyClassName regardless of the name of the actual 
header file in which the definition of MyClassName is contained.

Dimitri van Heesch's avatar
Dimitri van Heesch committed
126
If you want doxygen to show that the include file should be included using
127
quotes instead of angle brackets you should type:
Dimitri van Heesch's avatar
Dimitri van Heesch committed
128
\verbatim
129
/*! \class MyClassName myhdr.h "path/myhdr.h"
Dimitri van Heesch's avatar
Dimitri van Heesch committed
130 131 132 133 134
 *
 *  Docs for MyClassName
 */
\endverbatim

Dimitri van Heesch's avatar
Dimitri van Heesch committed
135
<li><b>How can I use tag files in combination with compressed HTML?</b>
136 137 138 139 140 141 142 143 144 145 146 147

If you want to refer from one compressed HTML file 
\c a.chm to another compressed HTML file 
called \c b.chm, the
link in \c a.chm must have the following format:
\verbatim
<a href="b.chm::/file.html">
\endverbatim
Unfortunately this only works if both compressed HTML files are in the same 
directory.

As a result you must rename the generated \c index.chm files for all projects
148
into something unique and put all <code>.chm</code> files in one directory.
149 150 151 152 153 154 155 156 157 158 159 160 161

Suppose you have a project \e a referring to a project \e b using tag file
\c b.tag, then you could rename the \c index.chm for project \e a into
\c a.chm and the \c index.chm for project \e b into \c b.chm. In the 
configuration file for project \e a you write:
\verbatim
TAGFILES = b.tag=b.chm::
\endverbatim
or you can use \c installdox to set the links as follows:
\verbatim
installdox -lb.tag@b.chm::
\endverbatim

Dimitri van Heesch's avatar
Dimitri van Heesch committed
162 163
<li><b>I don't like the quick index that is put above each HTML page, what do I do?</b>

164
You can disable the index by setting \ref cfg_disable_index "DISABLE_INDEX" to `YES`. Then you can
Dimitri van Heesch's avatar
Dimitri van Heesch committed
165
put in your own header file by writing your own header and feed that to
166
\ref cfg_html_header "HTML_HEADER".
Dimitri van Heesch's avatar
Dimitri van Heesch committed
167 168 169 170 171 172 173 174 175

<li><b>The overall HTML output looks different, while I only wanted to 
       use my own html header file</b>

You probably forgot to include the stylesheet <code>doxygen.css</code> that 
doxygen generates. You can include this by putting
\verbatim
<LINK HREF="doxygen.css" REL="stylesheet" TYPE="text/css">
\endverbatim
Dimitri van Heesch's avatar
Dimitri van Heesch committed
176
in the HEAD section of the HTML page.
Dimitri van Heesch's avatar
Dimitri van Heesch committed
177

178 179
<li><b>Why does doxygen use Qt?</b>

180
The most important reason is to have a platform abstraction for most 
181 182 183
Unices and Windows by means of the QFile, QFileInfo, QDir, QDate, 
QTime and QIODevice classes. 
Another reason is for the nice and bug free utility classes, like QList, 
184
QDict, QString, QArray, QTextStream, QRegExp, QXML etc. 
185

186 187 188 189 190 191 192 193 194 195
The GUI front-end doxywizard uses Qt for... well... the GUI!

<li><b>How can I exclude all test directories from my directory tree?</b>

Simply put an exclude pattern like this in the configuration file:

\verbatim
EXCLUDE_PATTERNS = */test/*
\endverbatim

196 197 198 199 200 201 202
<li><b>Doxygen automatically generates a link to the 
       class MyClass somewhere in the running text. 
       How do I prevent that at a certain place?</b>

Put a \% in front of the class name. Like this: \%MyClass. Doxygen will then
remove the % and keep the word unlinked.

203
<li><b>My favorite programming language is X. Can I still use doxygen?</b>
204 205 206

No, not as such; doxygen needs to understand the structure of what it reads. 
If you don't mind spending some time on it, there are several options:
Dimitri van Heesch's avatar
Dimitri van Heesch committed
207
- If the grammar of X is close to C or C++, then it is probably not too hard to
208 209 210
  tweak src/scanner.l a bit so the language is supported. This is done
  for all other languages directly supported by doxygen 
  (i.e. Java, IDL, C#, PHP).
Dimitri van Heesch's avatar
Dimitri van Heesch committed
211
- If the grammar of X is somewhat different than you can write an input
212 213 214
  filter that translates X into something similar enough to C/C++ for
  doxygen to understand (this approach is taken for VB, Object Pascal, and
  Javascript, see http://www.stack.nl/~dimitri/doxygen/download.html#helpers).
Dimitri van Heesch's avatar
Dimitri van Heesch committed
215
- If the grammar is completely different one could write a parser for X and 
216 217 218
  write a backend that produces a similar syntax tree as is done by 
  src/scanner.l (and also by src/tagreader.cpp while reading tag files).

Dimitri van Heesch's avatar
Dimitri van Heesch committed
219 220 221
<li><b>Help! I get the cryptic message 
 "input buffer overflow, can't enlarge buffer because scanner uses REJECT"</b>

222
This error happens when doxygen's lexical scanner has a rule that matches
Dimitri van Heesch's avatar
Dimitri van Heesch committed
223 224 225
more than 256K of input characters in one go. I've seen this happening 
on a very large generated file (\>256K lines), where the built-in preprocessor 
converted it into an empty file (with \>256K of newlines). Another case
Dimitri van Heesch's avatar
Dimitri van Heesch committed
226
where this might happen is if you have lines in your code with more than
Dimitri van Heesch's avatar
Dimitri van Heesch committed
227
256K characters. 
Dimitri van Heesch's avatar
Dimitri van Heesch committed
228

229
If you have run into such a case and want me to fix it, you
Dimitri van Heesch's avatar
Dimitri van Heesch committed
230 231
should send me a code fragment that triggers the message. To work around
the problem, put some line-breaks into your file, split it up into smaller 
232
parts, or exclude it from the input using EXCLUDE.
Dimitri van Heesch's avatar
Dimitri van Heesch committed
233

234 235 236 237 238
<li><b>When running make in the latex dir I get "TeX capacity exceeded". Now what?</b>

You can edit the texmf.cfg file to increase the default values of the 
various buffers and then run "texconfig init".

239 240
<li><b>Why are dependencies via STL classes not shown in the dot graphs?</b>

241 242
Doxygen is unaware of the STL classes, unless the 
option \ref cfg_builtin_stl_support "BUILTIN_STL_SUPPORT" is turned on.
243 244 245 246

<li><b>I have problems getting the search engine to work with PHP5 and/or windows</b>

Please read <a href="searchengine.html">this</a> for hints on where to look. 
247

Dimitri van Heesch's avatar
Dimitri van Heesch committed
248 249 250 251
<li><b>Can I configure doxygen from the command line?</b>

Not via command line options, but doxygen can read from <code>stdin</code>,
so you can pipe things through it. Here's an example how to override an option
252
in a configuration file from the command line (assuming a UNIX like environment):
Dimitri van Heesch's avatar
Dimitri van Heesch committed
253 254 255 256 257

\verbatim
( cat Doxyfile ; echo "PROJECT_NUMBER=1.0" ) | doxygen -
\endverbatim

258 259 260 261 262 263
For Windows the following would do the same:

\verbatim
( type Doxyfile & echo PROJECT_NUMBER=1.0 ) | doxygen.exe -
\endverbatim

Dimitri van Heesch's avatar
Dimitri van Heesch committed
264 265 266
If multiple options with the same name are specified then doxygen will use 
the last one. To append to an existing option you can use the += operator.

267
<li><b>How did doxygen get its name?</b>
268 269 270 271 272 273 274 275 276

Doxygen got its name from playing with the words 
documentation and generator.

\verbatim
documentation -> docs -> dox
generator -> gen
\endverbatim

Dimitri van Heesch's avatar
Dimitri van Heesch committed
277
At the time I was looking into \c lex and \c yacc, where a lot of things start with
278 279
"yy", so the "y" slipped in and made things pronounceable 
(the proper pronouncement is Docs-ee-gen, so with a long "e").
280

Dimitri van Heesch's avatar
Dimitri van Heesch committed
281 282 283
<li><b>What was the reason to develop doxygen?</b>

I once wrote a GUI widget based on the Qt library (it is still available at
284
http://sourceforge.net/projects/qdbttabular/ but hasn't been updated since 2002). 
Dimitri van Heesch's avatar
Dimitri van Heesch committed
285
Qt had nicely generated documentation (using an internal tool which 
286 287
<a href="http://rant.gulbrandsen.priv.no/udoc/history">they didn't want to release</a>) 
and I wrote similar docs by hand. 
Dimitri van Heesch's avatar
Dimitri van Heesch committed
288 289
This was a nightmare to maintain, so I wanted a similar tool. I looked at
Doc++ but that just wasn't good enough (it didn't support signals and
290
slots and did not have the Qt look and feel I had grown to like), 
Dimitri van Heesch's avatar
Dimitri van Heesch committed
291 292
so I started to write my own tool...

293
</ol>
Dimitri van Heesch's avatar
Dimitri van Heesch committed
294 295 296 297 298 299

\htmlonly
Go to the <a href="trouble.html">next</a> section or return to the
 <a href="index.html">index</a>.
\endhtmlonly

300 301
*/