foo.c

#include <pthread.h>
#include <stdlib.h>
#include <sys/time.h>
#include <stdio.h>

static void*
thread_func(void* arg)
{
    return NULL;
}

double
tv2double(struct timeval tv)
{
    return (double) tv.tv_sec + (double) tv.tv_usec / 1e6;
}

int
main()
{
    pthread_t thread;
    void* rv;
    unsigned iters = 1e6;

    struct timeval start;
    gettimeofday(&start, NULL);

    for (unsigned i = 0; i < iters; ++i) {
        if (pthread_create(&thread, NULL, thread_func, NULL))
            abort();
        if (pthread_join(thread, &rv))
            abort();
    }

    struct timeval end;
    gettimeofday(&end, NULL);

    double elapsed = tv2double(end) - tv2double(start);

    printf("%u iterations in %g seconds: %g iters/second\n",
           iters, elapsed, iters / elapsed);

    return 0;
}