gistfile1.h

#include <stdlib.h>
#include <stdio.h>
#include <sys/sysctl.h>
#include <sys/proc.h>
#include <sys/types.h>
#include <unistd.h>

// Return 1 if being debugged, 0 if not (or if debug status can't be determined).
int beingDebugged()
{       
	struct kinfo_proc *result;
	pid_t mypid = getpid();
	// Set up four-level query as described in man page.  Fourth arg is the PID of interest.
	int name[] = { CTL_KERN, KERN_PROC, KERN_PROC_PID, 0, 0 };
	name[3] = mypid;
	int debugged = 0;
	
	result = kinfo_ptr(name, ((sizeof(name) / sizeof(*name)) - 1), NULL);
	if (result == NULL) {
		return debugged;
	}
	if (result->kp_proc.p_flag & P_TRACED) {
		debugged = 1;
	}
	free(result);
	return debugged;
}