1 #define _GNU_SOURCE 2 3 #include <config.h> 4 #include <errno.h> 5 #include <stdio.h> 6 #include <stdlib.h> 7 #include <sys/ipc.h> 8 #include <sys/sem.h> 9 #include <time.h> 10 #include <unistd.h> 11 int main(int argc, char **argv) 12 { 13 int semid; 14 struct sembuf sop; 15 #ifdef HAVE_SEMTIMEDOP 16 struct timespec ts; 17 #endif 18 19 if ((semid = semget(IPC_PRIVATE, 1, 0600)) < 0) 20 { 21 perror("semget"); 22 exit(1); 23 } 24 25 sop.sem_num = 0; 26 sop.sem_op = 1; 27 sop.sem_flg = 0; 28 29 if (semop(semid, &sop, 1) < 0) 30 { 31 perror("semop"); 32 semctl(semid, 0, IPC_RMID); 33 exit(1); 34 } 35 36 if (semctl(semid, 0, GETVAL) != 1) 37 { 38 perror("semctl GETVAL"); 39 semctl(semid, 0, IPC_RMID); 40 exit(1); 41 } 42 43 if (semctl(semid, 0, GETPID) != getpid()) 44 { 45 perror("semctl GETPID"); 46 semctl(semid, 0, IPC_RMID); 47 exit(1); 48 } 49 50 /* The next call to semtimedop causes the program to hang on 51 ppc32-linux (Yellow Dog 4.0). I don't know why. Hence the 52 extended ifdef. */ 53 #if defined(HAVE_SEMTIMEDOP) && !defined(__powerpc__) 54 sop.sem_num = 0; 55 sop.sem_op = 0; 56 sop.sem_flg = 0; 57 58 ts.tv_sec = 0; 59 ts.tv_nsec = 1000000; 60 61 if (semtimedop(semid, &sop, 1, &ts) < 0 && errno != EAGAIN) 62 { 63 perror("semtimedop"); 64 semctl(semid, 0, IPC_RMID); 65 exit(1); 66 } 67 #endif 68 69 sop.sem_num = 0; 70 sop.sem_op = -1; 71 sop.sem_flg = 0; 72 73 if (semop(semid, &sop, 1) < 0) 74 { 75 perror("semop"); 76 semctl(semid, 0, IPC_RMID); 77 exit(1); 78 } 79 80 #ifdef HAVE_SEMTIMEDOP 81 sop.sem_num = 0; 82 sop.sem_op = 0; 83 sop.sem_flg = 0; 84 85 ts.tv_sec = 0; 86 ts.tv_nsec = 1000; 87 88 if (semtimedop(semid, &sop, 1, &ts) < 0) 89 { 90 perror("semtimedop"); 91 semctl(semid, 0, IPC_RMID); 92 exit(1); 93 } 94 #endif 95 96 if (semctl(semid, 0, IPC_RMID) < 0) 97 { 98 perror("semctl(IPC_RMID)"); 99 exit(1); 100 } 101 102 exit(0); 103 } 104
