10 lines
197 B
C
10 lines
197 B
C
#include <semaphore.h>
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#include "pthread_impl.h"
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int sem_trywait(sem_t *sem)
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{
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int val = sem->__val[0];
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if (val>0 && a_cas(sem->__val, val, val-1)==val) return 0;
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errno = EAGAIN;
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return -1;
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}
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