#include <stdio.h> #include <errno.h> #include <sys/sem.h> union semun { int val; /* Value for SETVAL */ struct semid_ds *buf; /* Buffer for IPC_STAT, IPC_SET */ unsigned short *array; /* Array for GETALL, SETALL */ struct seminfo *__buf; /* Buffer for IPC_INFO (Linux-specific) */ }; int main(void) { int rc, id; union semun un; struct semid_ds ds; struct seminfo info; id = semget(IPC_PRIVATE, 1, 0600); if (id < 0) return 77; printf("semget\\(IPC_PRIVATE, 1, 0600\\) += %d\n", id); un.buf = &ds; if (semctl(id, 0, IPC_STAT, un)) goto fail; printf("semctl\\(%d, 0, (IPC_64\\|)?IPC_STAT, \\[?%p\\]?\\) += 0\n", id, &ds); un.__buf = &info; int max = semctl(0, 0, SEM_INFO, un); if (max < 0) goto fail; printf("semctl\\(0, 0, (IPC_64\\|)?SEM_INFO, \\[?%p\\]?\\) += %d\n", &info, max); un.buf = &ds; rc = semctl(id, 0, SEM_STAT, un); if (rc != id) { /* * In linux < v2.6.24-rc1 the first argument must be * an index in the kernel's internal array. */ if (-1 != rc || EINVAL != errno) goto fail; printf("semctl\\(%d, 0, (IPC_64\\|)?SEM_STAT, \\[?%p\\]?\\)" " += -1 EINVAL \\(Invalid argument\\)\n", id, &ds); } else { printf("semctl\\(%d, 0, (IPC_64\\|)?SEM_STAT, \\[?%p\\]?\\)" " += %d\n", id, &ds, id); } rc = 0; done: if (semctl(id, 0, IPC_RMID, 0) < 0) return 1; printf("semctl\\(%d, 0, (IPC_64\\|)?IPC_RMID, \\[?0\\]?\\) += 0\n", id); return rc; fail: rc = 1; goto done; }