curlopt_tcp_fastopen(3) mojave man page | unix.com

CURLOPT_TCP_FASTOPEN(3) 				     curl_easy_setopt options					   CURLOPT_TCP_FASTOPEN(3)

NAME
       CURLOPT_TCP_FASTOPEN - enable TCP Fast Open

SYNOPSIS
       #include <curl/curl.h>

       CURLcode curl_easy_setopt(CURL *handle, CURLOPT_TCP_FASTOPEN, long enable);

DESCRIPTION
       Pass a long as parameter set to 1 to enable or 0 to disable.

       TCP Fast Open (RFC7413) is a mechanism that allows data to be carried in the SYN and SYN-ACK packets and consumed by the receiving end dur-
       ing the initial connection handshake, saving up to one full round-trip time (RTT).

DEFAULT
       0

PROTOCOLS
       All

EXAMPLE
       TODO

AVAILABILITY
       Added in 7.49.0. This option is currently only supported on Linux and  OS X El Capitan.

RETURN VALUE
       Returns CURLE_OK if fast open is supported by the operating system, otherwise returns CURLE_NOT_BUILT_IN.

libcurl 7.54.0							  April 03, 2016					   CURLOPT_TCP_FASTOPEN(3)