Set specific debug flags with the values provided for the process associated with the file descriptor. The flags that can be set are described in <sys/debug.h>. The argument is a pointer to an unsigned integer that specifies the debug flags to set. For example:
int flags; flags = _DEBUG_FLAG_KLC; /* Kill-on-Last-Close flag */ devctl( fd, DCMD_PROC_SET_FLAG, &flags, sizeof(flags), NULL);
To clear the debug flags, use DCMD_PROC_CLEAR_FLAG .