-if (!transport_headers_send(&cutthrough.addr, cutthrough.fd,
- cutthrough.addr.transport->add_headers,
- cutthrough.addr.transport->remove_headers,
- &cutthrough_write_chunk, topt_use_crlf,
- cutthrough.addr.transport->rewrite_rules,
- cutthrough.addr.transport->rewrite_existflags))
+tctx.tblock = cutthrough.addr.transport;
+tctx.addr = &cutthrough.addr;
+tctx.check_string = US".";
+tctx.escape_string = US"..";
+tctx.options = topt_use_crlf;
+
+if (!transport_headers_send(cutthrough.fd, &tctx, &cutthrough_write_chunk))