diff --git a/libc/include/sys/file.h b/libc/include/sys/file.h
index cf2f4b1..f414d34 100644
--- a/libc/include/sys/file.h
+++ b/libc/include/sys/file.h
@@ -25,14 +25,19 @@
  * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  * SUCH DAMAGE.
  */
+
 #ifndef _SYS_FILE_H_
 #define _SYS_FILE_H_
 
 #include <sys/cdefs.h>
 #include <sys/types.h>
 
-/* ANDROID: needed for flock() */
-#include <unistd.h>
 #include <fcntl.h>
 
+__BEGIN_DECLS
+
+int flock(int, int);
+
+__END_DECLS
+
 #endif /* _SYS_FILE_H_ */