This section describes on how to install Xdebug.

Xdebug's basic functions include the display of stack traces on error conditions, maximum nesting level protection and time tracking.

Xdebug replaces PHP's var_dump() function for displaying variables. Xdebug's version includes different colors for different types and places limits on the amount of array elements/object properties, maximum depth and string lengths. There are a few other functions dealing with variable display as well.

When Xdebug is activated it will show a stack trace whenever PHP decides to show a notice, warning, error etc. The information that stack traces display, and the way how they are presented, can be configured to suit your needs.

Xdebug allows you to log all function calls, including parameters and return values to a file in different formats.

Code coverage tells you which lines of script (or set of scripts) have been executed during a request. With this information you can for example find out how good your unit tests are.

Xdebug's built-in garbage collection statistics profiler allows you to find out when the PHP internal garbage collector triggers, how many variables it was able to clean up, how long it took, and how how much memory was actually freed.

Xdebug's built-in profiler allows you to find bottlenecks in your script and visualize those with an external tool such as KCacheGrind or WinCacheGrind.

Xdebug provides an interface for debugger clients that interact with running PHP scripts. This section explains how to set-up PHP and Xdebug to allow this, and introduces a few clients.

Frequently Asked Questions