1
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
4
<meta http-equiv="Content-Type" content="text/html; charset=US-ASCII">
5
<title>Running GLib Applications</title>
6
<meta name="generator" content="DocBook XSL Stylesheets V1.72.0">
7
<link rel="start" href="index.html" title="GLib Reference Manual">
8
<link rel="up" href="glib.html" title="GLib Overview">
9
<link rel="prev" href="glib-compiling.html" title="Compiling GLib Applications">
10
<link rel="next" href="glib-changes.html" title="Changes to GLib">
11
<meta name="generator" content="GTK-Doc V1.7 (XML mode)">
12
<link rel="stylesheet" href="style.css" type="text/css">
13
<link rel="chapter" href="glib.html" title="GLib Overview">
14
<link rel="chapter" href="glib-fundamentals.html" title="GLib Fundamentals">
15
<link rel="chapter" href="glib-core.html" title="GLib Core Application Support">
16
<link rel="chapter" href="glib-utilities.html" title="GLib Utilities">
17
<link rel="chapter" href="glib-data-types.html" title="GLib Data Types">
18
<link rel="chapter" href="tools.html" title="GLib Tools">
19
<link rel="index" href="ix01.html" title="Index">
20
<link rel="index" href="ix02.html" title="Index of deprecated symbols">
21
<link rel="index" href="ix03.html" title="Index of new symbols in 2.2">
22
<link rel="index" href="ix04.html" title="Index of new symbols in 2.4">
23
<link rel="index" href="ix05.html" title="Index of new symbols in 2.6">
24
<link rel="index" href="ix06.html" title="Index of new symbols in 2.8">
25
<link rel="index" href="ix07.html" title="Index of new symbols in 2.10">
26
<link rel="index" href="ix08.html" title="Index of new symbols in 2.12">
28
<body bgcolor="white" text="black" link="#0000FF" vlink="#840084" alink="#0000FF">
29
<table class="navigation" id="top" width="100%" summary="Navigation header" cellpadding="2" cellspacing="2"><tr valign="middle">
30
<td><a accesskey="p" href="glib-compiling.html"><img src="left.png" width="24" height="24" border="0" alt="Prev"></a></td>
31
<td><a accesskey="u" href="glib.html"><img src="up.png" width="24" height="24" border="0" alt="Up"></a></td>
32
<td><a accesskey="h" href="index.html"><img src="home.png" width="24" height="24" border="0" alt="Home"></a></td>
33
<th width="100%" align="center">GLib Reference Manual</th>
34
<td><a accesskey="n" href="glib-changes.html"><img src="right.png" width="24" height="24" border="0" alt="Next"></a></td>
36
<div class="refentry" lang="en">
37
<a name="glib-running"></a><div class="titlepage"></div>
38
<div class="refnamediv"><table width="100%"><tr>
40
<h2><span class="refentrytitle">Running GLib Applications</span></h2>
41
<p>Running GLib Applications —
42
How to run and debug your GLib application
45
<td valign="top" align="right"></td>
47
<div class="refsect1" lang="en">
48
<a name="id2687186"></a><h2>Running and debugging GLib Applications</h2>
49
<div class="refsect2" lang="en">
50
<a name="id2687192"></a><h3>Environment variables</h3>
52
GLib inspects a few of environment variables in addition to standard
53
variables like <code class="envar">LANG</code>, <code class="envar">PATH</code> or <code class="envar">HOME</code>.
55
<p><a name="G_FILENAME_ENCODING"></a><b><code class="envar">G_FILENAME_ENCODING</code>. </b>
56
This environment variable can be set to a comma-separated list of character
57
set names. GLib assumes that filenames are encoded in the first character
58
set from that list rather than in UTF-8. The special token "@locale" can be
59
used to specify the character set for the current locale.
61
<p><a name="G_BROKEN_FILENAMES"></a><b><code class="envar">G_BROKEN_FILENAMES</code>. </b>
62
If this environment variable is set, GLib assumes that filenames are in
63
the locale encoding rather than in UTF-8. G_FILENAME_ENCODING takes
64
priority over G_BROKEN_FILENAMES.
66
<p><a name="G_MESSAGES_PREFIXED"></a><b><code class="envar">G_MESSAGES_PREFIXED</code>. </b>
67
A list of log levels for which messages should be prefixed by the
68
program name and PID of the application. The default is to prefix
69
everything except <code class="literal">G_LOG_LEVEL_MESSAGE</code> and <code class="literal">G_LOG_LEVEL_INFO</code>.
71
<p><a name="G_DEBUG"></a><b><code class="envar">G_DEBUG</code>. </b>
72
If GLib has been configured with <code class="option">--enable-debug=yes</code>,
73
this variable can be set to a list of debug options, which cause GLib
74
to print out different types of debugging information.
76
<div class="variablelist"><table border="0">
77
<col align="left" valign="top">
80
<td><span class="term">fatal_warnings</span></td>
81
<td><p>Causes GLib to abort the program at the first call
82
to <a href="glib-Message-Logging.html#g-warning">g_warning</a>() or
83
<a href="glib-Message-Logging.html#g-critical">g_critical</a>(). This option is
84
special in that it doesn't require GLib to be configured with
85
debugging support.</p></td>
88
<td><span class="term">fatal_criticals</span></td>
89
<td><p>Causes GLib to abort the program at the first call
90
to <a href="glib-Message-Logging.html#g-critical">g_critical</a>(). This option is
91
special in that it doesn't require GLib to be configured with
92
debugging support.</p></td>
95
<td><span class="term">gc-friendly</span></td>
97
Newly allocated memory that isn't directly initialized, as well
98
as memory being freed will be reset to 0. The point here is to
99
allow memory checkers and similar programs that use bohem GC alike
100
algorithms to produce more accurate results.
101
This option is special in that it doesn't require GLib to be
102
configured with debugging support.
109
<p><a name="G_SLICE"></a><b><code class="envar">G_SLICE</code>. </b>
110
This environment variable allows reconfiguration of the #GSlice
113
<div class="variablelist"><table border="0">
114
<col align="left" valign="top">
116
<td><span class="term">always-malloc</span></td>
118
This will cause all slices allocated through g_slice_alloc() and
119
released by g_slice_free1() to be actually allocated via direct
120
calls to g_malloc() and g_free().
121
This is most useful for memory checkers and similar programs that
122
use bohem GC alike algorithms to produce more accurate results.
123
It can also be in conjunction with debugging features of the system's
124
malloc implementation such as glibc's MALLOC_CHECK_=2 to debug
125
erroneous slice allocation code.
131
<p><a name="G_RANDOM_VERSION"></a><b><code class="envar">G_RANDOM_VERSION</code>. </b>
132
If this environment variable is set to '2.0', the outdated
133
pseudo-random number seeding and generation algorithms from
134
GLib-2.0 are used instead of the new better ones. Use the GLib-2.0
135
algorithms only if you have sequences of numbers generated with
136
Glib-2.0 that you need to reproduce exactly.
138
<p><a name="LIBCHARSET_ALIAS_DIR"></a><b><code class="envar">LIBCHARSET_ALIAS_DIR</code>. </b>
139
Allows to specify a nonstandard location for the
140
<code class="filename">charset.aliases</code> file that is used by the
141
character set conversion routines. The default location is the
142
<em class="replaceable"><code>libdir</code></em> specified at compilation time.
144
<p><a name="G_WIN32_PRETEND_WIN9X"></a><b><code class="envar">G_WIN32_PRETEND_WIN9X</code>. </b>
145
Setting this variable to any value forces g_win32_get_windows_version()
146
to return a version code for Windows 9x. This is mainly an internal
147
debugging aid for GTK+ and GLib developers, to be able to check the
148
code paths for Windows 9x.
152
<div class="refsect2" lang="en">
153
<a name="id2688117"></a><h3>Traps and traces</h3>
155
<a class="indexterm" name="id2688125"></a>
156
<a class="indexterm" name="id2688132"></a>
157
<a class="indexterm" name="id2688139"></a>
158
Some code portions contain trap variables that can be set during debugging
159
time if GLib has been configured with <code class="option">--enable-debug=yes</code>.
160
Such traps lead to immediate code halts to examine the current program state
164
Currently, the following trap variables exist:
166
<pre class="programlisting">
167
static volatile gulong g_trap_free_size;
168
static volatile gulong g_trap_realloc_size;
169
static volatile gulong g_trap_malloc_size;
172
If set to a size > 0, <a href="glib-Memory-Allocation.html#g-free">g_free</a>(),
173
<a href="glib-Memory-Allocation.html#g-realloc">g_realloc</a>() and
174
<a href="glib-Memory-Allocation.html#g-malloc">g_malloc</a>() will be intercepted if the size
175
matches the size of the corresponding memory block. This will only work with
176
<code class="literal">g_mem_set_vtable (glib_mem_profiler_table)</code> upon startup
177
though, because memory profiling is required to match on the memory block sizes.
180
Note that many modern debuggers support conditional breakpoints, which achieve
181
pretty much the same. E.g. in gdb, you can do
183
<pre class="programlisting">
185
condition 1 n_bytes == 20
188
to break only on g_malloc() calls where the size of the allocated memory block
added
removed
docs/reference/glib/html/glib-running.html
