diff --git a/usr.bin/patch/backupfile.c b/usr.bin/patch/backupfile.c
index ecdca19e2a71..a35e6fd21dc8 100644
--- a/usr.bin/patch/backupfile.c
+++ b/usr.bin/patch/backupfile.c
@@ -22,7 +22,6 @@
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
-#include <unistd.h>
 
 #include "backupfile.h"