multiple timer to one process (without linking to rt) - c

Question

is there any way to register multiple timer to a single process? I have tried following code, yet without success. (Use "gcc -lrt" to compile it...). Program output nothing, which should atleast print "test". Is it possibly due to the dependence to linking to rt?
#define TT_SIGUSR1 (SIGRTMAX)
#define TT_SIGUSR2 (SIGRTMAX - 1)
#define TIME_INTERVAL_1 1
#define TIME_INTERVAL_2 2
#include <signal.h>
#include <time.h>
#include <stdio.h>
#include <unistd.h>
#include <linux/unistd.h>
#include <sys/syscall.h>
#include <sys/time.h>
#include <sys/types.h>
#include <sched.h>
#include <signal.h>
#include <setjmp.h>
#include <errno.h>
#include <assert.h>
timer_t create_timer(int signo) {
timer_t timerid;
struct sigevent se;
se.sigev_signo = signo;
if (timer_create(CLOCK_REALTIME, &se, &timerid) == -1) {
fprintf(stderr, "Failed to create timer\n");
exit(-1);
}
return timerid;
}
void set_timer(timer_t timerid, int seconds) {
struct itimerspec timervals;
timervals.it_value.tv_sec = seconds;
timervals.it_value.tv_nsec = 0;
timervals.it_interval.tv_sec = seconds;
timervals.it_interval.tv_nsec = 0;
if (timer_settime(timerid, 0, &timervals, NULL) == -1) {
fprintf(stderr, "Failed to start timer\n");
exit(-1);
}
return;
}
void install_sighandler2(int signo, void(*handler)(int)) {
struct sigaction sigact;
sigemptyset(&sigact.sa_mask);
sigact.sa_flags = SA_SIGINFO;
//register the Signal Handler
sigact.sa_sigaction = handler;
// Set up sigaction to catch signal first timer
if (sigaction(signo, &sigact, NULL) == -1)
{
printf("sigaction failed");
return -1;
}
}
void install_sighandler(int signo, void(*handler)(int)) {
sigset_t set;
struct sigaction act;
/* Setup the handler */
act.sa_handler = handler;
act.sa_flags = SA_RESTART;
sigaction(signo, &act, 0);
/* Unblock the signal */
sigemptyset(&set);
sigaddset(&set, signo);
sigprocmask(SIG_UNBLOCK, &set, NULL);
return;
}
void signal_handler(int signo) {
printf("receiving sig %d", signo);
}
int main()
{
printf("test");
timer_t timer1 = create_timer(TT_SIGUSR1);
timer_t timer2 = create_timer(TT_SIGUSR2);
set_timer(timer1, TIME_INTERVAL_1);
set_timer(timer2, TIME_INTERVAL_2);
install_sighandler2(TT_SIGUSR1, signal_handler);
install_sighandler(TT_SIGUSR2, signal_handler);
while (1)
;
return 0;
}

Answer 1

missing in create_timer: se.sigev_notify=SIGEV_SIGNAL;
two install_sighandler methods. Install_sighandler2 has a compler warning about mismatching pointer types.
while (1) will hog your processor, sleep.
#define TT_SIGUSR1 (SIGUSR1)
#define TT_SIGUSR2 (SIGUSR2)
#define TIME_INTERVAL_1 1
#define TIME_INTERVAL_2 2
#include <signal.h>
#include <time.h>
#include <stdio.h>
#include <unistd.h>
#include <linux/unistd.h>
#include <sys/syscall.h>
#include <sys/time.h>
#include <sys/types.h>
#include <sched.h>
#include <signal.h>
#include <setjmp.h>
#include <errno.h>
#include <assert.h>
#include <stdlib.h>
timer_t create_timer(int signo) {
timer_t timerid;
struct sigevent se;
se.sigev_notify=SIGEV_SIGNAL;
se.sigev_signo = signo;
if (timer_create(CLOCK_REALTIME, &se, &timerid) == -1) {
perror("Failed to create timer");
exit(-1);
}
return timerid;
}
void set_timer(timer_t timerid, int seconds) {
struct itimerspec timervals;
timervals.it_value.tv_sec = seconds;
timervals.it_value.tv_nsec = 0;
timervals.it_interval.tv_sec = seconds;
timervals.it_interval.tv_nsec = 0;
if (timer_settime(timerid, 0, &timervals, NULL) == -1) {
perror("Failed to start timer");
exit(-1);
}
return;
}
void install_sighandler(int signo, void(*handler)(int)) {
sigset_t set;
struct sigaction act;
/* Setup the handler */
act.sa_handler = handler;
act.sa_flags = SA_RESTART;
sigaction(signo, &act, 0);
/* Unblock the signal */
sigemptyset(&set);
sigaddset(&set, signo);
sigprocmask(SIG_UNBLOCK, &set, NULL);
return;
}
void signal_handler(int signo) {
printf("receiving sig %d\n", signo);
}
int main()
{
printf("test\n");
timer_t timer1 = create_timer(TT_SIGUSR1);
timer_t timer2 = create_timer(TT_SIGUSR2);
install_sighandler(TT_SIGUSR1, signal_handler);
install_sighandler(TT_SIGUSR2, signal_handler);
set_timer(timer1, TIME_INTERVAL_1);
set_timer(timer2, TIME_INTERVAL_2);
while (1) sleep(1);
return 0;
}