What does set -e mean in a bash script?

Question

I\'m studying the content of this preinst file that the script executes before that package is unpacked from its Debian archive (.deb) file.

The scr

Answer 1

I believe the intention is for the script in question to fail fast.

To test this yourself, simply type set -e at a bash prompt. Now, try running ls. You'll get a directory listing. Now, type lsd. That command is not recognized and will return an error code, and so your bash prompt will close (due to set -e).

Now, to understand this in the context of a 'script', use this simple script:

#!/bin/bash 
# set -e

lsd 

ls

If you run it as is, you'll get the directory listing from the ls on the last line. If you uncomment the set -e and run again, you won't see the directory listing as bash stops processing once it encounters the error from lsd.