Yesterday's meeting was a fun deep-dive into some `bash` quirks.

Mostly on how to determine if a script was sourced or run as an executable.

The reason being the use of `exit` statements as "gate clauses" to detect error conditions and abort instead of nesting the desired code inside if...elif...else...fi statements.

In a sourced script, `exit` will close the user's terminal.

We poured over a technique I found on StackOverflow years ago that checks for an error on calling `return` in an executed script (it's illegal there) and quits the program if the error does not occur.

Requires masking error messages generated when script is executable, running `set +e`, restoring the status of `set -e`, and other nonsense.

Hugh suggested that scripts should never be sourced unless specific conditions are desired. Not wrong, but the desire is to prevent users' terminal from closing on them, forcing the correct invocation.

Lennart came up with a clever technique, and even improved upon it by embedding it in a function.

I went with that method, then modified further to simply test for $0 == -bash, which is always true if the script was sourced.

Thanks everyone that joined the meeting and especially Lennart for his contribution.

Also, some clever shell tricks shared on the KWLUG mailing list recently, highly worth a quick read: