user64_msqid_ds Declarationstruct user64_msqid_ds { ... }; TopicsInstance Propertiesmsg_cbytesmsg_ctimemsg_firstmsg_lastmsg_lrpidmsg_lspidmsg_pad1msg_pad2msg_pad3msg_pad4msg_permmsg_qbytesmsg_qnummsg_rtimemsg_stime