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在网上找到一个简单例子,就是定时器周期性打印信息,在Ubuntu下编译且运行正常,而在arm开发板(AM437x)下运行,只打印一次信息,然后定时器就不起作用了?
代码如下:
#include <stdio.h>
#include <signal.h>
#include <time.h>
#include <string.h>
#include <stdlib.h>
#include <unistd.h>
void timer_thread(union sigval v)
{
printf("timer[CLOCK_MONOTONIC] function! %d\n", v.sival_int);
}
int main()
{
timer_t timerid;
struct sigevent evp;
memset(&evp, 0, sizeof(struct sigevent)); //清零初始化
evp.sigev_value.sival_int = 111; //也是标识定时器的,回调函数可以获得
evp.sigev_notify = SIGEV_THREAD; //线程通知的方式,派驻新线程
evp.sigev_notify_function = timer_thread; //线程函数地址
if (timer_create(CLOCK_MONOTONIC, &evp, &timerid) == -1)
{
perror("fail to timer_create");
exit(-1);
}
/* 第一次间隔it.it_value这么长,以后每次都是it.it_interval这么长,就是说it.it_value变0的时候会>装载it.it_interval的值 */
struct itimerspec it;
it.it_interval.tv_sec = 1; // 回调函数执行频率为1s运行1次
it.it_interval.tv_nsec = 0;
it.it_value.tv_sec = 1; // 倒计时1秒开始调用回调函数
it.it_value.tv_nsec = 0;
if (timer_settime(timerid, 0, &it, NULL) == -1)
{
perror("fail to timer_settime");
exit(-1);
}
//pause();
while (1);
return 0;
}
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