Using Shell Variables to Avoid Errors

Wed, 12 Aug 2026 00:00:00 +0000

Task

Create two files (release.txt, owner.txt) under a directory release-packages/northwind-api. The goal is to avoid typos by storing the path once in a variable.

Approach

Store the repeated path in a shell variable (TARGET_DIR), then reference it for both directory creation and file writes.

Solution

file.sh

#!/bin/bash
set -euo pipefail
TARGET_DIR=release-packages/northwind-api
mkdir -p "$TARGET_DIR"
echo 'release=2026.06.09' > "$TARGET_DIR/release.txt"
echo 'owner=platform' > "$TARGET_DIR/owner.txt"

Now run the script using chmod +x file.sh, then ./file.sh.

Verification

Cat file contents

$ cat release-packages/northwind-api/release.txt 
release=2026.06.09
$ cat release-packages/northwind-api/owner.txt
owner=platform

Verification isn’t just a formality. For example, a typo in the path or quoting can fail silently (e.g. create a wrongly named file) instead of throwing an error. So always confirm output rather than trusting the script ran correctly.

Shell-Scripting on Nerdsid.com

Using Shell Variables to Avoid Errors

Task

Approach

Solution

Verification