DMSG_IOCOMF_CLOSEALT
iocom->flags = DMSG_IOCOMF_RREQ | DMSG_IOCOMF_CLOSEALT;
if (iocom->alt_fd >= 0 && (iocom->flags & DMSG_IOCOMF_CLOSEALT)) {
iocom.flags &= ~DMSG_IOCOMF_CLOSEALT;