Description:
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When trying to do a PUT request using CURLOPT_INFILE followed by a GET, then the 
GET will encounter a "Warning: curl_setopt_array(): supplied argument is not a 
valid File-Handle resource" if the file handle has been closed.

This is a bug because you're supposed to free handles when you're not using them.

Setting NULL like with CURLOPT_HEADERFUNCTION (see 
http://curl.haxx.se/libcurl/c/curl_easy_setopt.html#CURLOPTHEADERFUNCTION) does 
not work, it gives "Warning: curl_setopt_array(): supplied argument is not a valid 
File-Handle resource".

See also Bug #44866 - leaking FDs is bad, bad program practice.

Test script:
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http://pastebin.com/XLJsZ9JH - line 44 is the CURLOPT_INFILE=>NULL line.

Expected result:
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Once CURLOPT_INFILE=>NULL has been set, I expect that the action of setting 
CURLOPT_INFILE=>$fp has been reversed (i.e. that curl has been reset to default),