Advanced Bash Scripting: Exit Codes, String Handling, Logic, and Control Flow
Exit Status and Special Variables
Every command you run in Bash returns an integer exit status captured in $?. A value of 0 means success; any thing else signals failure.
#!/usr/bin/env bash
# demo_exit.sh
whoami
echo "Last exit code: $?"
Save the snippet above as demo_exit.sh and run:
bash demo_exit.sh
You can use $? inside a scri ...
Posted on Mon, 05 Oct 2026 16:49:52 +0000 by Garth Farley