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<h4 class="subsection">3.2.3 Allocation Debugging</h4>

<p><a name="index-allocation-debugging-296"></a><a name="index-malloc-debugger-297"></a>
A complicated task when programming with languages which do not use
garbage collected dynamic memory allocation is to find memory leaks. 
Long running programs must assure that dynamically allocated objects are
freed at the end of their lifetime.  If this does not happen the system
runs out of memory, sooner or later.

   <p>The <code>malloc</code> implementation in the GNU C library provides some
simple means to detect such leaks and obtain some information to find
the location.  To do this the application must be started in a special
mode which is enabled by an environment variable.  There are no speed
penalties for the program if the debugging mode is not enabled.

<ul class="menu">
<li><a accesskey="1" href="Tracing-malloc.html#Tracing-malloc">Tracing malloc</a>:                How to install the tracing functionality. 
<li><a accesskey="2" href="Using-the-Memory-Debugger.html#Using-the-Memory-Debugger">Using the Memory Debugger</a>:     Example programs excerpts. 
<li><a accesskey="3" href="Tips-for-the-Memory-Debugger.html#Tips-for-the-Memory-Debugger">Tips for the Memory Debugger</a>:  Some more or less clever ideas. 
<li><a accesskey="4" href="Interpreting-the-traces.html#Interpreting-the-traces">Interpreting the traces</a>:       What do all these lines mean? 
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