Pass a long indicating the max. The set number will be used as the
maximum amount of simultaneously open connections that libcurl may keep in its
connection cache after completed use. By default libcurl will enlarge the size
for each added easy handle to make it fit 4 times the number of added easy
By setting this option, you can prevent the cache size from growing beyond the
limit set by you.
When the cache is full, curl closes the oldest one in the cache to prevent the
number of open connections from increasing.
This option is for the multi handles use only, when using the easy interface
you should instead use the CURLOPT_MAXCONNECTS(3) option.
See CURLMOPT_MAX_TOTAL_CONNECTIONS(3) for limiting the number of active