Source du programme¶

/* Effectuez l'édition des liens avec l'option "-lrt" */
#include <time.h>
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <pthread.h>
#include <string.h>
#include <errno.h>
#define handle_error(msg) \
        do { perror(msg); exit(EXIT_FAILURE); } while (0)
#define handle_error_en(en, msg) \
        do { errno = en; perror(msg); exit(EXIT_FAILURE); } while (0)
static void *
thread_start(void *arg)
{
    printf("Subthread starting infinite loop\n");
    for (;;)
        continue;
}
static void
pclock(char *msg, clockid_t cid)
{
    struct timespec ts;
    printf("%s", msg);
    if (clock_gettime(cid, &ts) == -1)
        handle_error("clock_gettime");
    printf("%4ld.%03ld\n", ts.tv_sec, ts.tv_nsec / 1000000);
}
int
main(int argc, char *argv[])
{
    pthread_t thread;
    clockid_t cid;
    int j, s;
    s = pthread_create(&thread, NULL, thread_start, NULL);
    if (s != 0)
        handle_error_en(s, "pthread_create");
    printf("Main thread sleeping\n");
    sleep(1);
    printf("Main thread consuming some CPU time...\n");
    for (j = 0; j < 2000000; j++)
        getppid();
    pclock("Process total CPU time: ", CLOCK_PROCESS_CPUTIME_ID);
    s = pthread_getcpuclockid(pthread_self(), &cid);
    if (s != 0)
        handle_error_en(s, "pthread_getcpuclockid");
    pclock("Main thread CPU time:   ", cid);
    /* The preceding 4 lines of code could have been replaced by:
       pclock("Main thread CPU time:   ", CLOCK_THREAD_CPUTIME_ID); */
    s = pthread_getcpuclockid(thread, &cid);
    if (s != 0)
        handle_error_en(s, "pthread_getcpuclockid");
    pclock("Subthread CPU time: 1    ", cid);
    exit(EXIT_SUCCESS);         /* Terminates both threads */
}