====== Apache - Troubleshooting - Using the Apache source code to locate problems ======

The source code is divided up into the following directories:

|$SRCROOT/server|The source code for the core server.|
|$SRCROOT/include|The header files for the core server.|
|$SRCROOT/srclib/apr|The source code for the portable runtime environment.|
|$SRCROOT/srclib/apr-util|The source code for the portable runtime utility code.|
|$SRCROOT/support|The source code for the utilities.|
|$SRCROOT/modules|Contains the source code for the modules.|

----

===== Using find to locate the C code that comprises that function (or macro) =====

If a stacktrace or debugging session shows that a specific routine is at fault, the **find** command can be used to locate the C code that comprises that function (or macro).

----

==== Locate the header file that contains a specific function prototype ====

To find the definition of the portable runtime function **apr_array_make**:

<code bash>
find . -name \*.h | xargs egrep "apr_array_make"
</code>

returns:

<code bash>
./srclib/apr/include/apr_tables.h:APR_DECLARE(apr_array_header_t *) apr_array_make(apr_pool_t *p, ...
...
</code>

<WRAP info>
**NOTE:**  This shows that the **apr_array_make** function prototype is located in the file **apr_tables.h**.
</WRAP>

----

==== Locate the source file that contains the function definition ====

Once the function prototype is located, the find and grep utilities can be used to to locate the source file that contains the function definition:

<code bash>
find . -name \*.c | xargs egrep "apr_array_header_t.*apr_array_make"
</code>

returns:

<code bash>
/srclib/apr/tables/apr_tables.c:APR_DECLARE(apr_array_header_t *) apr_array_make(apr_pool_t *p, ...
...
</code>

<WRAP info>
**NOTE:**  This shows that the function definition is located in the file **apr_tables.c**.

Depending on how functions (and macros) are defined, the results may require some additional visual processing.
</WRAP>