#include <stdio.h> #include <string.h> #include <errno.h> #include <sys/types.h> #include <sys/ipc.h> #include <sys/sem.h> int main(void) { int k, r; union semun { int val; struct semid_ds *buf; unsigned short int *array; struct seminfo *__buf; } sd; struct semid_ds sd_buf; k = semget(IPC_PRIVATE, 10, IPC_CREAT | 0666 ); printf("semget(IPC_CREAT) = %d\n", k); if (k < 0) { fprintf(stderr, "semget failed: %s\n", strerror(errno)); return 1; } sd.buf = &sd_buf; r = semctl(k, 0, IPC_STAT, sd); printf("semctl(k) = %d\n", r); if (r < 0) { perror("semctl IPC_STAT failed"); return 1; } printf("sem_nsems = %lu\n", sd_buf.sem_nsems); if (sd_buf.sem_nsems != 10) { fprintf(stderr, "failed: incorrect sem_nsems!\n"); return 1; } printf("succeeded\n"); return 0; }