c - Stop or Start setitimer -

i have set timer have 1 small issue, whenever alarm expires , catch_alarm function called, the timer stops , restarts when in returns main function . need perform benchmarks (packets received , send different interfaces) not include time takes processing not reflect true rx , tx rates accurately

the code sample shown:

#include <signal.h> #include <stdio.h> #include <string.h> #include <sys/time.h>  void catch_alarm (int sig) {     //stop timer here     printf("calling interrupt now\n");     sleep(1);     signal (sig, catch_alarm);     //start here again }  /*void waste (void) { printf("hello 1\n"); while(1) { printf("hello 2\n"); } printf("hello 3\n"); }*/    struct itimerval old; struct itimerval new;  int main(void) {     signal (sigalrm, catch_alarm);     new.it_interval.tv_sec = 1;     new.it_interval.tv_usec = 500000;     new.it_value.tv_sec = 1;     new.it_value.tv_usec = 500000;      old.it_interval.tv_sec = 0;     old.it_interval.tv_usec = 0;     old.it_value.tv_sec = 0;     old.it_value.tv_sec = 0;       if (setitimer (itimer_real, &new, &old) < 0)         printf("timer init failed\n");      else         printf("timer init succeeded\n");      while(1)     {         printf("in while loop\n");         //sleep(10);         //waste();         printf("resuming sleep\n");     }     return 0; } 

p.s: sigaction better suited here, if so, how ?