detect_proxy: only show proxy use if it had contents

diff --git a/lib/url.c b/lib/url.c
index 2491fa2da0a12cf8e281eef8f2b64523385181ea..eb1fc2220e855604a6a30b8f9c70332b38733ff9 100644 (file)
--- a/lib/url.c
+++ b/lib/url.c
@@ -2682,7 +2682,8 @@ static char *detect_proxy(struct connectdata *conn)
       proxy = curl_getenv(envp);
     }
   }
-  infof(conn->data, "Uses proxy env variable %s == '%s'\n", envp, proxy);
+  if(proxy)
+    infof(conn->data, "Uses proxy env variable %s == '%s'\n", envp, proxy);
 
   return proxy;
 }