CURLMOPT_PIPELINING(3)     Library Functions Manual     CURLMOPT_PIPELINING(3)

NAME
       CURLMOPT_PIPELINING - enable HTTP multiplexing

SYNOPSIS
       #include <curl/curl.h>

       CURLMcode curl_multi_setopt(CURLM *handle, CURLMOPT_PIPELINING, long bitmask);

DESCRIPTION
       Pass in the correct value in the bitmask parameter to instruct libcurl
       to enable multiplexing for this multi handle.

       With multiplexing enabled, libcurl attempts to do multiple transfers
       over the same connection when doing parallel transfers to the same
       hosts.

       CURLPIPE_NOTHING (0)
              Make no attempts at multiplexing.

       CURLPIPE_HTTP1 (1)
              This bit is deprecated and has no effect since version 7.62.0.

       CURLPIPE_MULTIPLEX (2)
              If this bit is set, libcurl tries to multiplex the new transfer
              over an existing connection if possible. This requires HTTP/2 or
              HTTP/3.

DEFAULT
       CURLPIPE_MULTIPLEX

PROTOCOLS
       This functionality affects http only

EXAMPLE
       int main(void)
       {
         CURLM *m = curl_multi_init();
         /* try HTTP/2 multiplexing */
         curl_multi_setopt(m, CURLMOPT_PIPELINING, CURLPIPE_MULTIPLEX);
       }

HISTORY
       The multiplex support bit was added in 7.43.0. HTTP/1 Pipelining
       support was disabled in 7.62.0.

       Since 7.62.0, CURLPIPE_MULTIPLEX is enabled by default.

       Before that, default was CURLPIPE_NOTHING.

AVAILABILITY
       Added in curl 7.16.0

RETURN VALUE
       curl_multi_setopt(3) returns a CURLMcode indicating success or error.

       CURLM_OK (0) means everything was OK, non-zero means an error occurred,
       see libcurl-errors(3).

SEE ALSO
       CURLMOPT_CHUNK_LENGTH_PENALTY_SIZE(3),
       CURLMOPT_CONTENT_LENGTH_PENALTY_SIZE(3), CURLMOPT_MAXCONNECTS(3),
       CURLMOPT_MAX_HOST_CONNECTIONS(3), CURLMOPT_MAX_PIPELINE_LENGTH(3),
       CURLMOPT_PIPELINING_SITE_BL(3)

libcurl                           2025-06-04            CURLMOPT_PIPELINING(3)