Removes an exception handler from a thread's chain of exception handlers.

#define INCL_DOSEXCEPTIONS
#include <os2.h>

PEXCEPTIONREGISTRATIONRECORD    pERegRec;  /*  A pointer to the exception registration record that describes the exception handler to be unregistered. */
APIRET                          ulrc;      /*  Return Code. */

ulrc = DosUnsetExceptionHandler(pERegRec);