31 lines
488 B
C
31 lines
488 B
C
//
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// Program to create shared semaphores
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//
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#include <semaphore.h>
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#include <stdio.h>
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#include <stdlib.h>
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#include <sys/wait.h>
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#include <unistd.h>
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int main() {
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sem_t sem;
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int pid;
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sem_init(&sem, 1, 0);
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if ((pid = fork()) != 0) {
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printf("Parent! Making my child wait for 1 second.\n");
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sleep(1);
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sem_post(&sem);
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} else {
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sem_wait(&sem);
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printf("Child! Waited 1 second for parent.\n");
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}
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if (pid != 0) {
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wait(NULL);
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sem_destroy(&sem);
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}
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}
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