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glibc  2.9
Functions
tst-sem7.c File Reference
#include <errno.h>
#include <fcntl.h>
#include <semaphore.h>
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>

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Functions

static void remove_sem (int status, void *arg)
int main (void)

Function Documentation

int main ( void  )

Definition at line 36 of file tst-sem7.c.

{
  sem_t *s;
  sem_t *s2;
  sem_t *s3;

  s = sem_open ("/glibc-tst-sem7", O_CREAT, 0600, 1);
  if (s == SEM_FAILED)
    {
      if (errno == ENOSYS)
       {
         puts ("sem_open not supported.  Oh well.");
         return 0;
       }

      /* Maybe the shm filesystem has strict permissions.  */
      if (errno == EACCES)
       {
         puts ("sem_open not allowed.  Oh well.");
         return 0;
       }

      printf ("sem_open: %m\n");
      return 1;
    }

  on_exit (remove_sem, (void *) "/glibc-tst-sem7");

  /* We have the semaphore object.  Now try again.  We should get the
     same address.  */
  s2 = sem_open ("/glibc-tst-sem7", O_CREAT, 0600, 1);
  if (s2 == SEM_FAILED)
    {
      puts ("2nd sem_open failed");
      return 1;
    }
  if (s != s2)
    {
      puts ("2nd sem_open didn't return the same address");
      return 1;
    }

  /* And again, this time without O_CREAT.  */
  s3 = sem_open ("/glibc-tst-sem7", 0);
  if (s3 == SEM_FAILED)
    {
      puts ("3rd sem_open failed");
      return 1;
    }
  if (s != s3)
    {
      puts ("3rd sem_open didn't return the same address");
      return 1;
    }

  /* Now close the handle.  Three times.  */
  if (sem_close (s2) != 0)
    {
      puts ("1st sem_close failed");
      return 1;
    }
  if (sem_close (s) != 0)
    {
      puts ("2nd sem_close failed");
      return 1;
    }
  if (sem_close (s3) != 0)
    {
      puts ("3rd sem_close failed");
      return 1;
    }

  return 0;
}

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static void remove_sem ( int  status,
void *  arg 
) [static]

Definition at line 29 of file tst-sem7.c.

{
  sem_unlink (arg);
}

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