PHP_FunctionCallTracer creates function calls debug trace.
Functions arguments, returned parameters
and watched variables are reported in the same section for each function call.
The trace is available as an array, or can be displayed or written in a file.
Traced variables can be processed by provided user functions for displaying purposes.
This package is not a replacement for full fledged PHP debuggers. It is
useful for (1) remote debugging, (2) to debug a complex sequence of function
calls, (3) to display non text variables in a user readable format.
Remote debugging is sometimes the only option to debug a package that
works fine on your system, e.g. a 32-bit OS, but breaks on a different system,
e.g. a 64-bit OS, which you have no access to. A remote user who has the
latter OS could run the package, then send you the trace for analysis.
It is sometimes difficult not to loose track of functions calls in some
live debugging sessions even with top notch PHP editor/debuggers. The trace
produced by this package may come handy and is easy to use in combination
with the source code to track calls and variables.
Some variables native format does not always display well, typically:
packed data and UTF-8 strings. They can be converted as they are being traced
to a readable format by provided user functions. For example: converting
binary strings to hexadecimal, or UTF-8 string to Unicode.