They're not. However, is_utf8 is to be avoided because it's too easy to use it when you shouldn't be doing that. In generaly, you should not be looking at the state of the UTF8 flag unless you're a Perl developer, or wish to learn about Perl's guts.

So as the average John Doe Perl hacker, what should I use to find out if a certain module or sub returns text strings or binary strings?

Very often that's only poorly documented, or not at all, and I don't think that "reading the source code" is a good advice either.

In reply to Re^5: Getting mad with CGI::Application and utf8 by moritz
in thread Getting mad with CGI::Application and utf8 by isync

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