Debugging

Debugging helps identify errors in shell scripts.

• Syntax check: bash -n script.sh

• Trace execution: bash -x script.sh (shows commands and expansions)

• Verbose: bash -v script.sh (prints lines as they are read)

• Set options:

  • set -e exit on error
  • set -u exit on undefined variable
  • set -o pipefail catch errors in pipelines

Input:

set -x
name="Pandu"
echo "User: $name"

Output:

+ name='Pandu'
+ echo 'User: Pandu'
User: Pandu

Explanation: set -x prints each command before execution, showing variable expansions.

References:

• https://man7.org/linux/man-pages/man1/bash.1.html