Output an error message when shmat() fails
Observed in with SELinux as the likely culprit. Without the message, the user saw a segfault with no apparent reason
@@ -78,6 +78,8 @@ USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
#include <sys/sysinfo.h>
#include <sys/syscall.h>
+#include <sys/types.h>
+#include <errno.h>
#include <sys/shm.h>
#include <fcntl.h>
#include <sched.h>
@@ -659,8 +661,9 @@ static void open_shmem(void) {
exit(1);
}
- if (shmid != -1) common = (shm_t *)shmat(shmid, NULL, 0);
-
+ if (shmid != -1) {
+ if ( (common = shmat(shmid, NULL, 0)) == (void*)-1) perror ("Attaching shared memory segment");
+ }
#ifdef DEBUG
fprintf(stderr, "Shared Memory id = %x Address = %p\n", shmid, common);
#endif
