proper way to detect shell exit code when errexit option set

Question

I prefer to write solid shell code, so the errexit & nounset is alway set.

The following code will stop at bad_command line

#!/bin/b         


        

Answer 1

In bash you can use the trap builtin which is quite nice. See https://unix.stackexchange.com/questions/79648/how-to-trigger-error-using-trap-command

Not sure how portable it is with other shells.. so YMMV