diff -r 7ea56f5700b8 -r f6f8b7c8919a tests/test-lfs-largefiles.t
--- a/tests/test-lfs-largefiles.t	Mon Nov 20 18:00:02 2017 -0500
+++ b/tests/test-lfs-largefiles.t	Mon Nov 20 18:05:15 2017 -0500
@@ -199,7 +199,7 @@
 commit.  By the time the commit occurs, the tracked file is smaller than the
 threshold (assuming it is > 41, so the standins don't become lfs objects).
 
-  $ yes | head -n 1048576 > large_by_size.bin
+  $ $PYTHON -c 'import sys ; sys.stdout.write("y\n" * 1048576)' > large_by_size.bin
   $ hg --config largefiles.minsize=1 ci -Am 'large by size'
   adding large_by_size.bin as a largefile
   $ hg manifest