// include:
#ifdef __DARWIN_UNIX03
#include <mach/mach_init.h>
#include <mach/task_policy.h>
#include <mach/task.h>
#include <mach/semaphore.h>
#else
#include <semaphore.h>
#endif

// global:
#ifdef __DARWIN_UNIX03
semaphore_t semaphore;
#else
sem_t semaphore;
#endif

// init:
#ifdef __DARWIN_UNIX03
    semaphore_create( mach_task_self(), &semaphore, 0, 0 );
#else
    sem_init( &semaphore, 0, 0 );
#endif

// signal/post:
#ifdef __DARWIN_UNIX03
    semaphore_signal( semaphore );
#else
    sem_post( &semaphore );
#endif

// wait:
#ifdef __DARWIN_UNIX03
    semaphore_wait( semaphore );
#else
    sem_wait( &semaphore );
#endif

#ifdef __DARWIN_UNIX03
    semaphore_destroy( mach_task_self(), semaphore );
#else
    sem_destroy( &semaphore );
#endif