Recently, an application echoed certain stuff at a random point of execution. Finding the exact statement turned out to be a problem: Too many statements emitted stuff.
Thefore, I registered a callback via ob_start() to let the callback echo a debug_backtrace() and exit the application.
Note, that I tried to disable output-buffering as the first statement of the callback.
Unfortunately, debug_backtrace() never returned anything. The app crashed as it called debug_backtrace() in the callback.
I even didn't manage to save the contents of debug_backtrace() to a file (as opposed to stdout).
Could someone explain why?