This intermediate course extends basic Bash scripts with reusable functions, controlled scope, cleanup handlers, parameter expansion, and arrays. Through five guided labs, you will organize script logic, separate text output from return status, respond to termination, manipulate strings without external tools, and process collections safely.
The final challenge combines those techniques in log_manager.sh: maintain a fixed array of prepared logs, derive .backup names inside a function, copy existing files, warn about missing targets, and remove a temporary report whenever the script exits.
What You Will Learn
- Define and call Bash functions and pass values through function arguments
- Protect script state with
localvariables instead of unintentionally changing globals - Return status codes from functions, capture
$?immediately, and branch on specific results - Register cleanup functions for SIGINT and EXIT with
trap - Slice, replace, and supply defaults for strings through Bash parameter expansion
- Declare arrays, append elements, expand all values, and iterate with safe quoting
- Derive backup filenames by replacing
.logwith.backupinside a function - Orchestrate cleanup, arrays, file tests, functions, and warnings in one executable script
Who This Course Is For
This course is for learners who have completed fundamental Bash scripting and want intermediate techniques for making small maintenance scripts more modular and predictable.
Prerequisites: Bash scripts, variables, positional arguments, conditionals, loops, file tests, exit codes, redirection, executable permissions, and basic file commands.
Learning environment: A provided Ubuntu-based LabEx terminal with Bash, editable project scripts, temporary-file and signal exercises, and three prepared application logs for the final challenge.
Frequently Asked Questions
How is the course structured?
Five labs provide guided practice. The sixth item is a less-guided challenge where you build one log_manager.sh that combines a cleanup trap, an archiving function, an array, string replacement, and a loop.
Does the final log manager compress, delete, or truly rotate logs?
No. It copies each prepared .log file to a sibling .backup name and preserves the original. It does not compress files, enforce retention, truncate logs, or configure logrotate.
Which events do the trap exercises handle?
The guided lab registers cleanup for SIGINT and EXIT so Ctrl+C and normal script termination remove a temporary file. The final challenge specifically requires an EXIT trap that deletes report.txt.
Can a Bash function return a string or other data with return?
Not in these exercises. Bash return carries an integer status from 0 to 255 for control flow; text is produced with echo or captured through command substitution.
