From 5b68e050e0f5073259fb20b3cd5cbd5cb38f53ac Mon Sep 17 00:00:00 2001
From: OmegaSquad82 <34405234+OmegaSquad82@users.noreply.github.com>
Date: Thu, 9 Jun 2022 04:11:24 +0200
Subject: [PATCH] Add usage of strict shell (#1841)

Co-authored-by: Rico Sta. Cruz <rstacruz@users.noreply.github.com>
---
 dockerfile.md | 14 ++++++++++++++
 1 file changed, 14 insertions(+)

diff --git a/dockerfile.md b/dockerfile.md
index 62a0a94c9..83b02e876 100644
--- a/dockerfile.md
+++ b/dockerfile.md
@@ -47,6 +47,20 @@ ADD file.xyz /file.xyz
 COPY --chown=user:group host_file.xyz /path/container_file.xyz
 ```
 
+### Run commands in strict shell
+
+```docker
+ENV my_var
+SHELL ["/bin/bash", "-euo", "pipefail", "-c"]
+
+# With strict mode:
+RUN false # fails build like using &&
+RUN echo "$myvar" # will throw error due to typo
+RUN true | false # will bail out of pipe
+```
+
+Using `shell` will turn on strict mode for shell commands.
+
 ### Onbuild
 
 ```docker