47 lines
836 B
C
47 lines
836 B
C
#include <stdio.h>
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#include <pthread.h>
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pthread_mutex_t a = PTHREAD_MUTEX_INITIALIZER;
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pthread_mutex_t b = PTHREAD_MUTEX_INITIALIZER;
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pthread_barrier_t bar;
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void *ba_lock(void *arg)
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{
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int ret, i;
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pthread_mutex_lock(&b);
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if (pthread_barrier_wait(&bar) == PTHREAD_BARRIER_SERIAL_THREAD)
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pthread_barrier_destroy(&bar);
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pthread_mutex_lock(&a);
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pthread_mutex_unlock(&a);
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pthread_mutex_unlock(&b);
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}
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int main(void)
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{
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pthread_t t;
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pthread_barrier_init(&bar, NULL, 2);
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if (pthread_create(&t, NULL, ba_lock, NULL)) {
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fprintf(stderr, "pthread_create() failed\n");
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return 1;
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}
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pthread_mutex_lock(&a);
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if (pthread_barrier_wait(&bar) == PTHREAD_BARRIER_SERIAL_THREAD)
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pthread_barrier_destroy(&bar);
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pthread_mutex_lock(&b);
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pthread_mutex_unlock(&b);
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pthread_mutex_unlock(&a);
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pthread_join(t, NULL);
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return 0;
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}
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