if ( tctx->chunk_cb(fd, tctx, hsize, 0) != OK
|| !transport_write_block(fd, deliver_out_buffer, hsize)
|| tctx->chunk_cb(fd, tctx, 0, tc_reap_prev) != OK
if ( tctx->chunk_cb(fd, tctx, hsize, 0) != OK
|| !transport_write_block(fd, deliver_out_buffer, hsize)
|| tctx->chunk_cb(fd, tctx, 0, tc_reap_prev) != OK