This consists of a simple PHP class file for sending debug messages, and an application that listens for and displays the messages as they arrive.
The script and application can be running on different machines as it simply uses sockets to send the data between them. I wrote it to send debug data from PHP scripts that were being called from within a Flash movie file. Because the script wasn’t being called directly from within a browser it was tricky to debug where errors were cropping up. This script and application let’s you capture that remotely.
It’s also great for debugging scripts that are outputting image data, as there again you can’t really write any debug data to the browser.
You will need the executable for the platform where you want to receive the debug messages as well as the PHP archive that contains the class file and example usage script. Both of these can be downloaded from the PHP Debug project page on Google Code.