sched_child_runs_first doesn't work

Rock Lee rockdotlee at gmail.com
Thu Dec 7 22:07:15 EST 2017


Hi,

I ran my test code but always got the father process run first, even
after setting sched_child_runs_first. Could anyone give me a hint?
Here is my test code.

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

int main(void)
{
    struct timeval tv;
    struct timezone tz;
    int err;
    pid_t ret = fork();

    if (ret == 0) {
        err = gettimeofday(&tv, &tz);
        if (!err)
            printf("child time sec %d, usec %d\n", tv.tv_sec, tv.tv_usec);

         printf("this child.\n");
    } else if (ret > 1) {
        err = gettimeofday(&tv, &tz);

        if (!err)
            printf("father time sec %d, usec %d\n", tv.tv_sec, tv.tv_usec);
        printf("this father.\n");
    } else
        printf("err!!\n");
    return 0;
}


-- 
Cheers,
Rock



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