/* * (C) Finite State Machine Labs Inc. 2000 business@fsmlabs.com * * Released under the terms of GPL 2. * Open RTLinux makes use of a patented process described in * US Patent 5,995,745. Use of this process is governed * by the Open RTLinux Patent License which can be obtained from * www.fsmlabs.com/PATENT or by sending email to * licensequestions@fsmlabs.com */#include <stdio.h>#include <errno.h>#include <sys/time.h>#include <sys/types.h>#include <fcntl.h>#include <unistd.h>#include <sys/ioctl.h>struct timeval torig, t1, t2;int main(void){#define US(x) ( ((unsigned long long)(x).tv_sec*1000000) + (unsigned long long)(x).tv_usec )	gettimeofday(&torig, 0);	t1 = torig;	do {		gettimeofday(&t2, 0);		if (US(t2) < US(t1)) {			fprintf(stderr, "Linux time went backwards\n");			return -1;		}		t1 = t2;	} while (US(t2) < (US(torig) + (unsigned long long) 10 * 1000000));	return 0;}