C++ (Cpp) ACE_SV_Semaphore_Complex::tryacquire Examples

Example #1

File: Semaphores_2.cpp Project: azraelly/knetwork

static int
child (char *shm)
{
  // Both semaphores are initially created with a count of 0, i.e.,
  // they are "locked."
  ACE_SV_Semaphore_Complex mutex (SEM_KEY_1, ACE_SV_Semaphore_Complex::ACE_CREATE, 0);
  ACE_SV_Semaphore_Complex synch (SEM_KEY_2, ACE_SV_Semaphore_Complex::ACE_CREATE, 0);

  // Perform "busy waiting" here until we acquire the semaphore.  This
  // isn't really a good design -- it's just to illustrate that you
  // can do non-blocking acquire() calls with the ACE System V
  // semaphore wrappers.
  while (mutex.tryacquire () == -1)
    if (errno == EAGAIN)
      ACE_DEBUG ((LM_DEBUG, "spinning in child!\n"));
    else
      ACE_ERROR_RETURN ((LM_ERROR, "child mutex.tryacquire"), 1);

  for (char *s = (char *) shm; *s != '\0'; s++)
    ACE_DEBUG ((LM_DEBUG, "%c", *s));

  ACE_DEBUG ((LM_DEBUG, "\n"));

  if (synch.release () == -1)
    ACE_ERROR_RETURN ((LM_ERROR, "child synch.release"), 1);
  return 0;
}

Example #2

File: SV_Shared_Memory_Test.cpp Project: BackupTheBerlios/pyasynchio-svn

static int
child (char *shm)
{
  int result;

  ACE_SV_Semaphore_Complex mutex;

  // This semaphore is initially created with a count of 0, i.e., it
  // is "locked."
  result = mutex.open (SEM_KEY_1,
                       ACE_SV_Semaphore_Complex::ACE_CREATE,
                       0);
  ACE_ASSERT (result != -1);

  ACE_SV_Semaphore_Complex synch;
  // This semaphore is initially created with a count of 0, i.e., it
  // is "locked."
  result = synch.open (SEM_KEY_2,
                       ACE_SV_Semaphore_Complex::ACE_CREATE,
                       0);
  ACE_ASSERT (result != -1);

  // Perform "busy waiting" here until we acquire the semaphore.  This
  // isn't really a good design -- it's just to illustrate that you
  // can do non-blocking acquire() calls with the ACE System V
  // semaphore wrappers.
  while ((result = mutex.tryacquire ()) == -1)
    if (errno == EAGAIN)
      ACE_DEBUG ((LM_DEBUG,
                  ACE_TEXT ("(%P) spinning in child!\n")));
    else
      {
        ACE_ERROR ((LM_ERROR,
                    ACE_TEXT ("(%P) child mutex.tryacquire")));
        ACE_ASSERT (result != -1);
      }

  for (int i = 0; i < SHMSZ; i++)
    ACE_ASSERT (SHMDATA[i] == shm[i]);

  result = synch.release ();
  ACE_ASSERT (result != -1);

  return 0;
}

Example #3

static int
child (char *shm)
{
  ACE_SV_Semaphore_Complex sem (SEM_KEY, ACE_SV_Semaphore_Complex::ACE_CREATE, 0, 2);

  while (sem.tryacquire (0) == -1)
    if (errno == EAGAIN)
      ACE_DEBUG ((LM_DEBUG, "spinning in client!\n"));
    else
      ACE_ERROR_RETURN ((LM_ERROR, "client mutex.tryacquire(0)"), 1);

  for (char *s = (char *) shm; *s != '\0'; s++)
    ACE_DEBUG ((LM_DEBUG, "%c", *s));

  ACE_DEBUG ((LM_DEBUG, "\n"));

  if (sem.release (1) < 0)
    ACE_ERROR ((LM_ERROR, "client sem.release(1)"));
  return 0;
}