I now get the 'unchecked input' part. And I can sort of understand issues with tainting. About the C code: you're talking about C code that tries to interpret the invalid utf-8, right? Because C's basic string operations don't look at the encoding, so they are just as (un)safe when you send them a non-utf8 marked string with miscellaneous binary data in it.

update: about the (removed) line: "Another possibility is careless use of utf8::upgrade()."

That's removed because utf8::upgrade() is always safe (if you start out with valid utf-8 flags), right?

"What should it profit a man, if he should win a flame war, yet lose his cool?"

In reply to Re^5: A UTF8 round trip with MySQL by Joost
in thread A UTF8 round trip with MySQL by clinton

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