easy:SetOpt_DNS_Cache_Timeout -- set life-time for DNS cache entries
Pass a value, this sets the timeout in seconds. Name resolves will be kept in memory and used for this number of seconds. Set to zero to completely disable caching, or set to -1 to make the cached entries remain forever. By default, libcurl caches this info for 60 seconds.

The name resolve functions of various libc implementations don't re-read name server information unless explicitly told so (for example, by calling res_init). This may cause libcurl to keep using the older server even if DHCP has updated the server info, and this may look like a DNS cache issue to the casual libcurl-app user.

Note that DNS entries have a "TTL" property but libcurl doesn't use that. This DNS cache timeout is entirely speculative that a name will resolve to the same address for a certain small amount of time into the future.

input value

Show TOC