--- hashcash-0.28/hashcash.c	2003-09-18 22:13:38.000000000 -0600
+++ hashcash-0.28-patched/hashcash.c	2004-01-30 15:14:32.000000000 -0700
@@ -12,7 +12,7 @@
 #if defined( THINK_C )
     #include <console.h>
     #include <unix.h>
-#elif defined( unix ) || defined( VMS )
+#elif defined( unix ) || defined( VMS ) || defined( __APPLE__ )
     #include <unistd.h>
 #elif defined ( WIN32 )
     #include <io.h>