smb_sel_t
const smb_sel_t *sel;
if (stp->smbst_hdr->smbh_len < sizeof (smb_sel_t) - sizeof (uint8_t))
sel = (smb_sel_t *)(uintptr_t)stp->smbst_hdr;
len = stp->smbst_hdr->smbh_len - sizeof (smb_sel_t) + sizeof (uint8_t);