struct msqid_ds { struct ipc_perm msg_perm; time_t msg_stime; time_t msg_rtime; time_t msg_ctime; unsigned long msg_cbytes; long __unused1; msgqnum_t msg_qnum; long __unused2; msglen_t msg_qbytes; long __unused3; pid_t msg_lspid; pid_t msg_lrpid; unsigned long long __unused[2]; };