semaphore.c

#include <native/sem.h>

#define SEM_INIT 1       /* Initial semaphore count */
#define SEM_MODE S_FIFO  /* Wait by FIFO order */

RT_SEM sem_desc;

void foo (void)

{
    int err;

    /* Create a semaphore; we could also have attempted to bind to
       some pre-existing object, using rt_sem_bind() instead of
       creating it. */

    err = rt_sem_create(&sem_desc,"MySemaphore",SEM_INIT,SEM_MODE);

    for (;;) {

        /* Now, wait for a semaphore unit... */
        rt_sem_p(&sem_desc,TM_INFINITE);

        /* ... */

        /* then release it. */
        rt_sem_v(&sem_desc);

        /* ... */
    }
}

void cleanup (void)

{
    rt_sem_delete(&sem_desc);
}

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