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#define _GNU_SOURCE
#include <config.h>
#include <errno.h>
#include <stdio.h>
#include <stdlib.h>
#include <sys/ipc.h>
#include <sys/sem.h>
#include <time.h>
int main(int argc, char **argv)
{
int semid;
struct sembuf sop;
#ifdef HAVE_SEMTIMEDOP
struct timespec ts;
#endif
if ((semid = semget(IPC_PRIVATE, 1, 0600)) < 0)
{
perror("semget");
exit(1);
}
sop.sem_num = 0;
sop.sem_op = 1;
sop.sem_flg = 0;
if (semop(semid, &sop, 1) < 0)
{
perror("semop");
semctl(semid, 0, IPC_RMID);
exit(1);
}
/* The next call to semtimedop causes the program to hang on
ppc32-linux (Yellow Dog 4.0). I don't know why. Hence the
extended ifdef. */
#if defined(HAVE_SEMTIMEDOP) && !defined(__powerpc__)
sop.sem_num = 0;
sop.sem_op = 0;
sop.sem_flg = 0;
ts.tv_sec = 0;
ts.tv_nsec = 1000000;
if (semtimedop(semid, &sop, 1, &ts) < 0 && errno != EAGAIN)
{
perror("semtimedop");
semctl(semid, 0, IPC_RMID);
exit(1);
}
#endif
sop.sem_num = 0;
sop.sem_op = -1;
sop.sem_flg = 0;
if (semop(semid, &sop, 1) < 0)
{
perror("semop");
semctl(semid, 0, IPC_RMID);
exit(1);
}
#ifdef HAVE_SEMTIMEDOP
sop.sem_num = 0;
sop.sem_op = 0;
sop.sem_flg = 0;
ts.tv_sec = 0;
ts.tv_nsec = 1000;
if (semtimedop(semid, &sop, 1, &ts) < 0)
{
perror("semtimedop");
semctl(semid, 0, IPC_RMID);
exit(1);
}
#endif
if (semctl(semid, 0, IPC_RMID) < 0)
{
perror("semctl(IPC_RMID)");
exit(1);
}
exit(0);
}
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