<html><head><meta name="color-scheme" content="light dark"></head><body><pre style="word-wrap: break-word; white-space: pre-wrap;">On Tiger, TCP_KEEPALIVE only appears if neither _XOPEN_SOURCE nor
_POSIX_C_SOURCE is defined. Instead of dealing with other possible
ramifications of undefining those, just pop in the TCP_KEEPALIVE
definition from &lt;netinet/tcp.h&gt;.

--- fmacros.h.orig
+++ fmacros.h
@@ -6,7 +6,7 @@
 
 #if defined(__APPLE__) &amp;&amp; defined(__MACH__)
 /* Enable TCP_KEEPALIVE */
-#define _DARWIN_C_SOURCE
+#define TCP_KEEPALIVE 0x10
 #endif
 
 #endif
</pre></body></html>