linux高编信号-------setitimer()getitimer()

Posted 2020-10-07 muzihuan

/*************************
 *功能：获取时钟间隔
 *参数：which：设置哪个时钟
 *             ITIMER_REAL:实时递减，超时发送SIGALRM信号
 *             ITIMER_VIRTURL:虚拟时钟，超时发送SIGVALRM时钟
 *             ITIMER_PROF: 
 * **********************/
int getitimer(int which, struct itimerval *curr_value);


/*************************
 *功能：设置时钟间隔
 *参数：which：设置哪个时钟
 *             ITIMER_REAL:实时递减，超时发送SIGALRM信号
 *             ITIMER_VIRTURL:虚拟时钟，超时发送SIGVALRM时钟
 *             ITIMER_PROF: 
 *      new_value:新的时钟
 *      old_value:旧时间
 * **********************/
int setitimer(int which, const struct itimerval *new_value,struct itimerval *old_value);

//时间赋值是原子操作
struct itimerval {
    struct timeval it_interval; /* next value */
    struct timeval it_value;    /* current value */
};

struct timeval {
    long tv_sec;                /* seconds */
    long tv_usec;               /* microseconds */
};