mysql_debug()
void mysql_debug(const char *debug)
Use this function to set debugging if the client was
compiled with debugging. The set of options used by default is
'd:t:o,logname‘. See Table 16-1 at the end of the list of options
for the mysqldump utility in Chapter 16 for an
explanation of these flags and others that may be used. Here is an
example:
...
mysql_debug("d:t:o,filename");
...The filename given could include the path to the log file where debugging information is to be written.