Notes on HTTP_PROXY env var

doc/03-cli.md

@@ -179,10 +179,15 @@ directory to something other than `vendor/bin`.
 This env var controls the time composer waits for commands (such as git
 commands) to finish executing. The default value is 60 seconds.
 
-### HTTP_PROXY
+### http_proxy or HTTP_PROXY
 
 If you are using composer from behind an HTTP proxy, you can use the standard
-`HTTP_PROXY` or `http_proxy` env vars. Simply set it to the URL of your proxy.
+`http_proxy` or `HTTP_PROXY` env vars. Simply set it to the URL of your proxy.
 Many operating systems already set this variable for you.
 
+Using `http_proxy` (lowercased) or even defining both might be preferrable since
+some tools like git or curl will only use the lower-cased `http_proxy` version.
+Alternatively you can also define the git proxy using
+`git config --global http.proxy <proxy url>`.
+
 &larr; [Libraries](02-libraries.md)  |  [Schema](04-schema.md) &rarr;

src/Composer/Util/StreamContextFactory.php

@@ -34,7 +34,7 @@ final class StreamContextFactory
         // Handle system proxy
         if (isset($_SERVER['HTTP_PROXY']) || isset($_SERVER['http_proxy'])) {
             // Some systems seem to rely on a lowercased version instead...
-            $proxy = isset($_SERVER['HTTP_PROXY']) ? $_SERVER['HTTP_PROXY'] : $_SERVER['http_proxy'];
+            $proxy = isset($_SERVER['http_proxy']) ? $_SERVER['http_proxy'] : $_SERVER['HTTP_PROXY'];
 
             // http(s):// is not supported in proxy
             $proxy = str_replace(array('http://', 'https://'), array('tcp://', 'ssl://'), $proxy);