timer 信号中断

#include     // for printf()
#include    // for pause()
#include    // for signal()
#include    // for memset()
#include // struct itimeral. setitimer()
#include
void printMsg(int);

int main() {
  // Get system call result to determine successful or failed
  int res = 0;
  pthread_t a;
  // Register printMsg to SIGALRM
  signal(SIGALRM, pthread_create(&a,NULL,(void*)printMsg,NULL));
 
  struct itimerval tick;
  // Initialize struct
  memset(&tick, 0, sizeof(tick));
  // Timeout to run function first time
  tick.it_value.tv_sec = 1;  // sec
  tick.it_value.tv_usec =0 ; // micro sec.
  // Interval time to run function
  tick.it_interval.tv_sec = 1;
  tick.it_interval.tv_usec =0 ;
  // Set timer, ITIMER_REAL : real-time to decrease timer,
  //                          send SIGALRM when timeout
  res = setitimer(ITIMER_REAL, &tick, NULL);
  if (res) {
    printf("Set timer failed!!\n");
  }

  // Always sleep to catch SIGALRM signal
  while(1) {
     pause();
  }

  return 0 ; 
}

void printMsg(int num) {
  printf("%s","Hello World!!\n");
}