Build properly with different versions of libc by including all posix APIs

in header definitions.


git-svn-id: http://svn.fedorahosted.org/svn/corosync/trunk@3030 fd59a12c-fef9-0310-b244-a6a79926bd2f

configure.ac

@@ -278,7 +278,7 @@ case "$host_os" in
 		AC_DEFINE_UNQUOTED([COROSYNC_LINUX], [1],
 				   [Compiling for Linux platform])
 		OS_CFLAGS=""
-		OS_CPPFLAGS=""
+		OS_CPPFLAGS="-D_GNU_SOURCE"
 		OS_LDFLAGS=""
 		OS_DYFLAGS="-rdynamic"
 		DARWIN_OPTS=""