Linux POSIX 定时器 （timer_create)

#include <stdlib.h>#include <unistd.h>#include <stdio.h>#include <signal.h>#include <time.h>#include <string.h>//#define CLOCKID CLOCK_REALTIME#define CLOCKID    CLOCK_MONOTONIC#define SIG SIGRTMIN   //实时信号，可靠信号#define errExit(msg)    do { perror(msg); exit(EXIT_FAILURE); \        } while (0)static voidprint_siginfo(siginfo_t *si){    timer_t *tidp;    int or;    tidp = si->si_value.sival_ptr;    printf("    sival_ptr = %p; ", si->si_value.sival_ptr);    printf("    *sival_ptr = 0x%lx\n", (long) *tidp);    or = timer_getoverrun(*tidp);    if (or == -1)        errExit("timer_getoverrun");    else        printf("    overrun count = %d\n", or);}static voidhandler(int sig, siginfo_t *si, void *uc){    /* Note: calling printf() from a signal handler is not              strictly correct, since printf() is not async-signal-safe;              see signal(7)     */    printf("Caught signal %d\n", sig);    print_siginfo(si);    //signal(sig, SIG_IGN);}static voidhandler2(union sigval v){    timer_t *tidp;    tidp=v.sival_ptr;    printf("Caught handler2 0x%lx\n",*(long *)tidp);//打印传递的参数}typedef  void (*sigHandler)(int , siginfo_t *, void *);typedef  void (*pthHandler)(union sigval);//定时器通知方式为信号的处理方式int testTimerSign(timer_t *pTimerid, struct itimerspec ts, int sig, sigHandler handler){    struct sigevent evp;    struct sigaction sa;    int ret=0;    printf("Establishing handler for signal %d\n", SIG);    sa.sa_flags = SA_SIGINFO;    sa.sa_sigaction = handler;    sigemptyset(&sa.sa_mask);    //安装信号处理函数    if (sigaction(sig, &sa, NULL) == -1)    {        perror("testTimerSign:sigaction");        ret=-1;    }    memset(&evp,0,sizeof(evp));    evp.sigev_notify =SIGEV_SIGNAL;    evp.sigev_signo = sig;    evp.sigev_value.sival_ptr = pTimerid; //传递的参数,指针型    ret = timer_create(CLOCKID, &evp, pTimerid);    if(ret) {        perror("timer_create");    }    printf("timer ID is 0x%lx\n", (long) *pTimerid);    //  ts.it_value.tv_sec = 1;    //  ts.it_value.tv_nsec = 10000000;    //  ts.it_interval.tv_sec = its.it_value.tv_sec;    //  ts.it_interval.tv_nsec = its.it_value.tv_nsec;    printf("testTimerSign:start timer\n");    ret = timer_settime(*pTimerid, 0, &ts, NULL);    if(ret) {        perror("timer_settime\n");    }    return ret;}//定时器通知方式为线程方式int testTimerThread(timer_t *pTimerid,struct itimerspec its,pthHandler handler){    struct sigevent sev;    int ret=0;    memset(&sev,0,sizeof(sev));    sev.sigev_notify = SIGEV_THREAD;    sev.sigev_notify_function=handler;//处理函数    sev.sigev_value.sival_ptr = pTimerid;//传递给处理函数的参数，指针型    //sev.sigev_value.sival_int=timerid;    if (timer_create(CLOCKID, &sev, pTimerid) == -1)    {        perror("timer_create\n");        ret=-1;    }    printf("timer ID is 0x%lx\n", (long) *pTimerid);    //  its.it_value.tv_sec = 1;    //  its.it_value.tv_nsec = 10000000;    //  its.it_interval.tv_sec = its.it_value.tv_sec;    //  its.it_interval.tv_nsec = its.it_value.tv_nsec;    if (timer_settime(*pTimerid, 0, &its, NULL) == -1)    {        perror("timer_settime\n");        ret=-1;    }    return ret;}intmain(int argc, char *argv[]){    timer_t timerid1,timerid2;    struct  itimerspec ts1,ts2;    if (argc != 2) {        fprintf(stderr, "Usage: %s <sleep-secs>\n",                argv[0]);        exit(EXIT_FAILURE);    }    ts1.it_value.tv_sec =  1;  //定时器初次触发时间    ts1.it_value.tv_nsec = 0;    ts1.it_interval.tv_sec = ts1.it_value.tv_sec;  //定时器周期性间隔时间    ts1.it_interval.tv_nsec = ts1.it_value.tv_nsec;    ts2.it_value.tv_sec =  4;  //定时器初次触发时间    ts2.it_value.tv_nsec = 0;    ts2.it_interval.tv_sec = 2;  //定时器周期性间隔时间    ts2.it_interval.tv_nsec = 0;    testTimerSign(&timerid1,ts1,SIG,handler);    testTimerThread(&timerid2,ts2,handler2);    /*     *     * Sleep for a while; meanwhile, the timer may expire              multiple times     */    printf("Sleeping for %d seconds\n", atoi(argv[1]));    while(1)        sleep(atoi(argv[1]));    exit(EXIT_SUCCESS);}