SMB3_SIG_OFFS
thdr->b_rptr += SMB3_SIG_OFFS;
thdr->b_rptr -= SMB3_SIG_OFFS;
thdr->b_rptr += SMB3_SIG_OFFS;
thdr->b_rptr -= SMB3_SIG_OFFS;
(void) smb_mbc_poke(out_mbc, SMB3_SIG_OFFS, "#c",