External abort handler
called if an exception was raised
Note, that normal program execution isn't possible at this time.
typedef void (*PHDL_ABORT)(char* abortmsg);
External trap handler
called if an exception was raised and no abort handler was defined
After that the program aborts. ( used by the xaron project )
typedef void (*PHDL_TRAP)();
External memory handler
called once if memory allocation failed in order to release memory
typedef void (*PHDL_FREEMEM)(size_t cnt);