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CURLMOPT_MAX_HOST_CONNECTIONS(3)                     curl_multi_setopt options

NAME
       CURLMOPT_MAX_HOST_CONNECTIONS - set max number of connections to a
       single host

SYNOPSIS
       #include <curl/curl.h>

       CURLMcode curl_multi_setopt(CURLM *handle,
       CURLMOPT_MAX_HOST_CONNECTIONS, long max);

DESCRIPTION
       Pass a long to indicate max. The set number will be used as the maximum
       amount of simultaneously open connections to a single host (a host
       being the same as a host name + port number pair). For each new session
       to a host, libcurl will open a new connection up to the limit set by
       CURLMOPT_MAX_HOST_CONNECTIONS(3). When the limit is reached, the
       sessions will be pending until a connection becomes available. If
       CURLMOPT_PIPELINING(3) is enabled, libcurl will try to pipeline if the
       host is capable of it.

       The default max value is 0, unlimited.  However, for backwards
       compatibility, setting it to 0 when CURLMOPT_PIPELINING(3) is 1 will
       not be treated as unlimited. Instead it will open only 1 connection and
       try to pipeline on it.

       This set limit is also used for proxy connections, and then the proxy
       is considered to be the host for which this limit counts.

       When more transfers are added to the multi handle than what can be
       performed due to the set limit, they will be queued up waiting for
       their chance. When that happens, the CURLOPT_TIMEOUT_MS(3) timeout will
       be counted inclusive of the waiting time, meaning that if you set a too
       narrow timeout in such a case the transfer might never even start
       before it times out.

       Even in the queued up situation, the CURLOPT_CONNECTTIMEOUT_MS(3)
       timeout is however treated as a per-connect timeout.

DEFAULT
       0

PROTOCOLS
       HTTP(S)

EXAMPLE
       CURLM *m = curl_multi_init();
       /* do no more than 2 connections per host */
       curl_multi_setopt(m, CURLMOPT_MAX_HOST_CONNECTIONS, 2L);

AVAILABILITY
       Added in 7.30.0

RETURN VALUE
       Returns CURLM_OK if the option is supported, and CURLM_UNKNOWN_OPTION
       if not.

SEE ALSO
       CURLMOPT_MAXCONNECTS(3), CURLMOPT_MAX_TOTAL_CONNECTIONS(3),

libcurl 7.76.0                  March 17, 2021
                                              CURLMOPT_MAX_HOST_CONNECTIONS(3)