From 3bb1291fbd4f938bb9b7b3c2fe48b029ee0152d3 Mon Sep 17 00:00:00 2001
From: Daniel Stenberg <daniel@haxx.se>
Date: Thu, 10 Feb 2011 22:21:57 +0100
Subject: [PATCH] --keepalive-time: warn if not supported properly

Since the feature requires support for TCP_KEEPIDLE and TCP_KEEPINTVL to
function as documented, it now warns if that support is missing when the
option is used.
---
 src/main.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/src/main.c b/src/main.c
index cfff1f9825..1c707f89fc 100644
--- a/src/main.c
+++ b/src/main.c
@@ -1764,6 +1764,10 @@ static int sockoptcallback(void *clientp, curl_socket_t curlfd,
           warnf(clientp, "Could not set TCP_KEEPINTVL!\n");
           return 0;
         }
+#endif
+#if !defined(TCP_KEEPIDLE) || !defined(TCP_KEEPINTVL)
+        warnf(clientp, "Keep-alive functionality somewhat crippled due to "
+              "missing support in your operating system!\n");
 #endif
       }
     }