Debugging in PHP
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Debugging in PHP
PHP Manual

## About debugging in PHP

PHP does not have an internal debugging facility. You can use one of the external debuggers though. The » Zend IDE includes a debugger, and there are also some free debugger extensions like DBG at » http://dd.cron.ru/dbg/, the » Advanced PHP Debugger (APD) or » Xdebug.

Debugging in PHP
Configure options
Debugging in PHP
PHP Manual