but the precise answer to your question is that hello.pl must be placed in the directory cgi-bin
Er... no. The precise answer is that hello.pl must be placed in whatever directory the configuration of the web server has mapped to the URL /cgi-bin/. This is often a directory called cgi-bin but without examining the web server configuration files you can't be 100% sure. It's possible that it's not mapped onto any directory at all.
Typically this will be found in the public_html directory
Well, only on servers that have user directories enabled. And even then only on ones that allow individual users to have cgi-bin directories. That's pretty rare in my experience.
"The first rule of Perl club is you do not talk about
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