CURLMOPT_MAX_PIPELINE_LENGTH - maximum number of requests in a pipeline
CURLMcode curl_multi_setopt(CURLM *handle, CURLMOPT_MAX_PIPELINE_LENGTH,
No function since pipelining was removed in 7.62.0.
Pass a long. The set max number will be used as the maximum
amount of outstanding requests in an HTTP/1.1 pipelined connection. This
option is only used for HTTP/1.1 pipelining, not for HTTP/2
When this limit is reached, libcurl will use another connection to
the same host (see CURLMOPT_MAX_HOST_CONNECTIONS(3)), or queue the
request until one of the pipelines to the host is ready to accept a request.
Thus, the total number of requests in-flight is
CURLM *m = curl_multi_init();
/* set a more conservative pipe length */
curl_multi_setopt(m, CURLMOPT_MAX_PIPELINE_LENGTH, 3L);
Returns CURLM_OK if the option is supported, and CURLM_UNKNOWN_OPTION if not.