easy:SetOpt_HeaderOpt -- set how to send HTTP headers
Pass a value that is a bitmask of options of how to deal with headers. The two mutually exclusive options are:

the headers specified in #CURLOPT_HTTPHEADER will be used in requests both to servers and proxies. With this option enabled, #CURLOPT_PROXYHEADER will not have any effect.

makes #CURLOPT_HTTPHEADER headers only get sent to a server and not to a proxy. Proxy headers must be set with #CURLOPT_PROXYHEADER to get used. Note that if a non-CONNECT request is sent to a proxy, libcurl will send both server headers and proxy headers. When doing CONNECT, libcurl will send #CURLOPT_PROXYHEADER headers only to the proxy and then #CURLOPT_HTTPHEADER headers only to the server.

input value

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