diff -up mozilla-beta/ipc/chromium/src/base/file_util.cc.old mozilla-beta/ipc/chromium/src/base/file_util.cc
--- mozilla-beta/ipc/chromium/src/base/file_util.cc.old	2012-01-25 13:48:11.000000000 +0100
+++ mozilla-beta/ipc/chromium/src/base/file_util.cc	2012-01-25 13:52:25.096659244 +0100
@@ -8,7 +8,7 @@
 #include <io.h>
 #endif
 #include <stdio.h>
-#if defined(ANDROID)
+#if defined(ANDROID) || defined(OS_POSIX)
 #include <unistd.h>
 #endif