it's show that /proc/`pid`/exe is not always valid.

no_proc_self_exe.c

#include <stdlib.h>
#include <stdio.h>
#include <unistd.h>
#include <pthread.h>

#define NUM_THREADS 5

void func(void *a)
{
    printf("/proc/%ld/exe\n", getpid());
    //the /proc/getpid()/exe will can't read
    sleep(100);
    pthread_exit(NULL);
}

int main()
{
    pthread_t t;
    pthread_create(&t, NULL, func, 0);
    pthread_exit(NULL);
}