.\" ************************************************************************** .\" * _ _ ____ _ .\" * Project ___| | | | _ \| | .\" * / __| | | | |_) | | .\" * | (__| |_| | _ <| |___ .\" * \___|\___/|_| \_\_____| .\" * .\" * Copyright (C) 1998 - 2020, Daniel Stenberg, , 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. .\" * .\" ************************************************************************** .\" .TH CURLOPT_TCP_NODELAY 3 "November 04, 2020" "libcurl 7.74.0" "curl_easy_setopt options" .SH NAME CURLOPT_TCP_NODELAY \- set the TCP_NODELAY option .SH SYNOPSIS #include CURLcode curl_easy_setopt(CURL *handle, CURLOPT_TCP_NODELAY, long nodelay); .SH DESCRIPTION Pass a long specifying whether the TCP_NODELAY 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 (MSS) 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), "