Mapserver WMS Client, libcurl, caching

[Christopher Schmidt]

libcurl in mapserver sends Pragma:no-cache headers in the wms client.  
This means that it's impossible to use Squid to cache data coming from 
another WMS server to speed things up.  I've spent the past two hours 
trying to work out how to change this and failed --   it seems like 
it's somewhere in maphttp.c, but I can't get it to do what I want.  
The Pragma header needs to be removed, in some way like 

  headers = curl_slist_append(headers, "Pragma:");  
  
The Apple documentation [1] is a good reference doc to look at: it seems 
that up until last year, sending Pragma: no-cache was default for 
everywhere with curl. This is no longer the case with the curl binary,
but it's still the default in libcurl. I can't wrap my head around the 
code to find out where I need to change it --  but if anyone has any 
ideas or patches they want me to try, I'm game.

[1] http://developer.apple.com/documentation/Darwin/Reference/ManPages/man3/libcurl-tutorial.3.html 

-- 
Christopher Schmidt
Web Developer