리눅스에서 여러개의 타이머 구현 샘플

#include <cstdio> #include <cstdlib> #include <cstring> #include <sys/time.h> #include <unistd.h> #include <signal.h> #include <time.h> timer_t firstTimerID; timer_t secondTimerID; timer_t thirdTimerID; static void timerHandler( int sig, siginfo_t *si, void *uc ) {     timer_t *tidp;     tidp = (void**)(si->si_value.sival_ptr);     if ( *tidp == firstTimerID )         printf("2ms\n");     else if ( *tidp == secondTimerID )         printf("10ms\n");     else if ( *tidp == thirdTimerID )         printf("100ms\n"); } static int makeTimer( timer_t *timerID, int expireMS, int intervalMS ) {     struct sigevent te;     struct itimerspec its;     struct sigaction sa;     int sigNo = SIGRTMIN;     /* Set up signal handler. */     sa.sa_flags = SA_SIGINFO;     sa.sa_sigaction = timerHandler;     sigemptyset(&sa.sa_mask);     if (sigaction(sigNo, &sa, NULL) == -1) {         perror("sigaction");     }     /* Set and enable alarm */     te.sigev_notify = SIGEV_SIGNAL;     te.sigev_signo = sigNo;     te.sigev_value.sival_ptr = timerID;     timer_create(CLOCK_REALTIME, &te, timerID);     its.it_interval.tv_sec = 0;     its.it_interval.tv_nsec = intervalMS * 1000000;     its.it_value.tv_sec = 0;     its.it_value.tv_nsec = expireMS * 1000000;     timer_settime(*timerID, 0, &its, NULL);     return 1; } int main() {     makeTimer(&firstTimerID, 500, 500); //2ms     makeTimer(&secondTimerID,900, 900); //10ms     //makeTimer(&thirdTimerID, 100, 100); //100ms     while(1)     {     }     return 0; }