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/* this tests whether we can use a sysv shared memory segment
as needed for the sysv varient of FAST_SHARE_MODES */
#include <unistd.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <sys/ipc.h>
#include <sys/shm.h>
#define KEY 0x963796
#define SIZE (32*1024)
main()
{
int id;
int *buf;
int count=7;
#ifdef LINUX
if (sizeof(struct shmid_ds) == 52) {
printf("WARNING: You probably have a broken set of glibc2 include files - disabling sysv shared memory\n");
exit(1);
}
#endif
id = shmget(KEY, 0, 0);
if (id != -1) {
if (shmctl(id, IPC_RMID, 0) != 0) exit(1);
}
if (fork() == 0) {
/* uggh - need locking */
sleep(2);
/* get an existing area */
id = shmget(KEY, 0, 0);
if (id == -1) exit(1);
buf = (int *)shmat(id, 0, 0);
if (buf == (int *)-1) exit(1);
while (count-- && buf[6124] != 55732) sleep(1);
if (count <= 0) exit(1);
buf[1763] = 7268;
exit(0);
}
id = shmget(KEY, SIZE, IPC_CREAT | IPC_EXCL | 0600);
if (id == -1) exit(1);
buf = (int *)shmat(id, 0, 0);
if (buf == (int *)-1) exit(1);
buf[6124] = 55732;
while (count-- && buf[1763] != 7268) sleep(1);
shmctl(id, IPC_RMID, 0);
if (count <= 0) exit(1);
exit(0);
}
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