71 lines
1.8 KiB
Markdown
71 lines
1.8 KiB
Markdown
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---
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c: Copyright (C) Daniel Stenberg, <daniel@haxx.se>, et al.
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SPDX-License-Identifier: curl
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Title: CURLMOPT_MAX_TOTAL_CONNECTIONS
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Section: 3
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Source: libcurl
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See-also:
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- CURLMOPT_MAXCONNECTS (3)
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- CURLMOPT_MAX_HOST_CONNECTIONS (3)
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---
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# NAME
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CURLMOPT_MAX_TOTAL_CONNECTIONS - max simultaneously open connections
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# SYNOPSIS
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~~~c
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#include <curl/curl.h>
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CURLMcode curl_multi_setopt(CURLM *handle, CURLMOPT_MAX_TOTAL_CONNECTIONS,
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long amount);
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~~~
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# DESCRIPTION
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Pass a long for the **amount**. The set number is used as the maximum number
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of simultaneously open connections in total using this multi handle. For each
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new session, libcurl might open a new connection up to the limit set by
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CURLMOPT_MAX_TOTAL_CONNECTIONS(3). When the limit is reached, new
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sessions are held pending until there are available connections. If
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CURLMOPT_PIPELINING(3) is enabled, libcurl can try multiplexing if the
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host is capable of it.
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When more transfers are added to the multi handle than what can be performed
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due to the set limit, they get queued up waiting for their chance. When that
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happens, the CURLOPT_TIMEOUT_MS(3) timeout is counted inclusive of the
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waiting time, meaning that if you set a too narrow timeout in such a case the
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transfer might never even start before it times out.
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Even in the queued up situation, the CURLOPT_CONNECTTIMEOUT_MS(3)
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timeout is however treated as a per-connect timeout.
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# DEFAULT
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The default value is 0, which means that there is no limit. It is then simply
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controlled by the number of easy handles added.
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# PROTOCOLS
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All
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# EXAMPLE
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~~~c
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int main(void)
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{
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CURLM *m = curl_multi_init();
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/* never do more than 15 connections */
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curl_multi_setopt(m, CURLMOPT_MAX_TOTAL_CONNECTIONS, 15L);
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}
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~~~
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# AVAILABILITY
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Added in 7.30.0
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# RETURN VALUE
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Returns CURLM_OK if the option is supported, and CURLM_UNKNOWN_OPTION if not.
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