From 7c327798923f5a797319c379c875d09f800150d4 Mon Sep 17 00:00:00 2001
From: Benson Muite <bkmgit@users.noreply.github.com>
Date: Mon, 13 Feb 2023 16:37:23 +0300
Subject: [PATCH] Do not overwrite a file that is used later

Make a copy of the file.
---
 _episodes/04-pipefilter.md | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/_episodes/04-pipefilter.md b/_episodes/04-pipefilter.md
index 53999df81..485635cee 100644
--- a/_episodes/04-pipefilter.md
+++ b/_episodes/04-pipefilter.md
@@ -286,7 +286,8 @@ the output of `head` must be the file with the fewest lines.
 > to the same file. For example:
 >
 > ~~~
-> $ sort -n lengths.txt > lengths.txt
+> $ cp lengths.txt lengths-copy.txt
+> $ sort -n lengths-copy.txt > lengths-copy.txt
 > ~~~
 > {: .language-bash}
 >