ttys_time.c

来自「足球机器人自动程序」· C语言 代码 · 共 60 行

#include "cmd.h"
#include "tty.h"
#include "ctrl.h"

#include <sys/poll.h>
#include <sys/time.h>
#include <time.h>

char cmd = RV;
int fd;
char rbuf[4];

int main() {

	struct timeval tv, tvo;
	double t;

	// init ttys
	fd = ttys_init(0);

	// init ctrl
	ctrl_init(fd);

	gettimeofday(&tvo, NULL);
	if (write(fd, &cmd, 1) != 1) {
		fprintf(stderr, "write error\n");
		return -1;
	}

	struct pollfd ufds = {fd, POLLIN};
	int n;

	int i = 0;
	for (; i<300; ++i) {
		if (poll(&ufds, 1, -1) <= 0) {
			fprintf(stderr, "poll error\n");
			return -1;
		}

		if ((n = read(fd, rbuf, sizeof(rbuf))) <= 0) {
			fprintf(stderr, "read error\n");
			return -1;
		}

		gettimeofday(&tv, NULL);
		t = tv.tv_sec - tvo.tv_sec;
		t += (double)(tv.tv_usec - tvo.tv_usec) / 1e6;
		tvo = tv;
		printf("%d\t%f\n", n, t);

		if (write(fd, &cmd, 1) != 1) {
			fprintf(stderr, "write error\n");
			return -1;
		}
	}

	return 0;
}