I don't understand Perl's "-e" operator

Question

I see Perl scripts using `-e`, for example `unless -e` I understand the `unless` loop, but not the `-e` part. An explanation would be nice. When should `-e` be used?

Accepted Answer

It's to check if a file exists.

http://perldoc.perl.org/functions/-X.html

I don't understand Perl's "-e" operator

Solution

Problem