You may enable remote debugging for all scripts by editing the configuration file php.ini, or you may use the debugger_on function, described in Chapter 8, "I/O Functions." Once enabled, PHP will attempt to connect to a remote host and port each time a script is run.
You will need a port listening program to get the debugging information. There are numerous free port listeners for Windows. I've found Port Listener by Hauke X to work well. Similar programs exist for UNIX as well.
All debugging messages are sent to the listening host, regardless of the error reporting level set in php.ini. Messages are sent in a special format
date time host(pid) type:message-data
followed by a linefeed.
The date is in the format YYYY-MM-DD