Norman Vine <nhv@users.sourceforge.net>:

freddrake · freddrake · commit 51d9036cc8cd · 2000-10-06T15:37:06.000Z
tcp.h is not available on CygWin, so do not try to include it there. This closes SourceForge patch #101802.
diff --git a/Modules/socketmodule.c b/Modules/socketmodule.c
@@ -122,7 +122,7 @@ Socket methods:
 #include <netdb.h>
 #include <sys/socket.h>
 #include <netinet/in.h>
-#ifndef __BEOS__
+#if !(defined(__BEOS__) || defined(__CYGWIN__))
 #include <netinet/tcp.h>
 #endif
 
