diff --git a/extra/io/unix/mmap/mmap.factor b/extra/io/unix/mmap/mmap.factor
index ada1f94d87..4b015a071e 100755
--- a/extra/io/unix/mmap/mmap.factor
+++ b/extra/io/unix/mmap/mmap.factor
@@ -4,7 +4,7 @@ USING: alien io io.files kernel math system unix io.unix.backend
 io.mmap ;
 IN: io.unix.mmap
 
-: open-r/w ( path -- fd ) O_RDWR file-mode open dup io-error ;
+: open-r/w ( path -- fd ) O_RDWR file-mode open-file ;
 
 : mmap-open ( length prot flags path -- alien fd )
     >r f -roll r> open-r/w [ 0 mmap ] keep