.\" **************************************************************************
.\" *                                  _   _ ____  _
.\" *  Project                     ___| | | |  _ \| |
.\" *                             / __| | | | |_) | |
.\" *                            | (__| |_| |  _ <| |___
.\" *                             \___|\___/|_| \_\_____|
.\" *
.\" * Copyright (C) Daniel Stenberg, <daniel@haxx.se>, et al.
.\" *
.\" * This software is licensed as described in the file COPYING, which
.\" * you should have received as part of this distribution. The terms
.\" * are also available at https://curl.se/docs/copyright.html.
.\" *
.\" * You may opt to use, copy, modify, merge, publish, distribute and/or sell
.\" * copies of the Software, and permit persons to whom the Software is
.\" * furnished to do so, under the terms of the COPYING file.
.\" *
.\" * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
.\" * KIND, either express or implied.
.\" *
.\" * SPDX-License-Identifier: curl
.\" *
.\" **************************************************************************
.\"
.TH CURLOPT_TCP_NODELAY 3 "30 Jun 2016" libcurl libcurl
.SH NAME
CURLOPT_TCP_NODELAY \- the TCP_NODELAY option
.SH SYNOPSIS
.nf
#include <curl/curl.h>

CURLcode curl_easy_setopt(CURL *handle, CURLOPT_TCP_NODELAY, long nodelay);
.fi
.SH DESCRIPTION
Pass a long specifying whether the \fITCP_NODELAY\fP option is to be set or
cleared (1L = set, 0 = clear). The option is set by default. This will have no
effect after the connection has been established.

Setting this option to 1L will disable TCP's Nagle algorithm on this
connection. The purpose of this algorithm is to try to minimize the number of
small packets on the network (where "small packets" means TCP segments less
than the Maximum Segment Size for the network).

Maximizing the amount of data sent per TCP segment is good because it
amortizes the overhead of the send. However, in some cases small segments may
need to be sent without delay. This is less efficient than sending larger
amounts of data at a time, and can contribute to congestion on the network if
overdone.
.SH DEFAULT
1
.SH PROTOCOLS
All
.SH EXAMPLE
.nf
CURL *curl = curl_easy_init();
if(curl) {
  curl_easy_setopt(curl, CURLOPT_URL, "https://example.com");
  /* leave Nagle enabled */
  curl_easy_setopt(curl, CURLOPT_TCP_NODELAY, 0);
  curl_easy_perform(curl);
}
.fi
.SH AVAILABILITY
Always. The default was changed to 1 from 0 in 7.50.2.
.SH RETURN VALUE
Returns CURLE_OK
.SH "SEE ALSO"
.BR CURLOPT_SOCKOPTFUNCTION "(3), " CURLOPT_TCP_KEEPALIVE "(3), "