Is setitimer() call inherited by children

I'm writing a code forking (number of 3, 5, ... indefinite number). I wish my program to end after the time specified(parent kills firstly its children then itself probably by calling _exit which is also sig-safe). I mean in signal handler I kill whole children by kill() then call waitpid() for all since both are kind of async-signal-safe function. To do that, I'm using setitimer(ITIMER_REAL, &timer, NULL before forking.

So is it inherited by the forked children?

If it is not inherited, could you show a source?

If it is inherited, do all children end as well after the time is taken? In addition, actually I don't want the case.

Not inherited.

The POSIX spec for fork explicitly mentions that timers are not inherited and that XSI (timer_create/timer_settime) timers are reset:

• [XSI] [Option Start] Interval timers shall be reset in the child process. [Option End]
• Per-process timers created by the parent shall not be inherited by the child process.

A test program like:

#include <unistd.h>
#include <stdio.h>
#include <signal.h>
#include <signal.h>
#include <string.h>
#include <sys/time.h>

void h(int Sig)
{
    char pid[20];
    sprintf(pid,"%d\n",(int)getpid());
    (void)write(1,pid,strlen(pid));
}
int main()
{
    if(0>sigaction(SIGALRM,&(struct sigaction){.sa_handler=h},0)) return perror("sigaction"),1;
    if(0>setitimer(ITIMER_REAL, &(struct itimerval){.it_value.tv_sec=1},0)) return perror("setitimer"),1;
    pid_t ch; if(0>(ch=fork())) return perror("fork"),1;
    pause();
    if(ch){
        sleep(1);
        kill(ch,SIGTERM);
    }
    _exit(0);
}

shows the handler runs only in the parent—it prints only one pid.