Aaron Sherman <ajs@[...].com>  writes:

>  Is anyone aware of any limitations in 5.8.1 that would lead to a problem
>  using substr on utf8 strings? I'm getting lots of:
>  
>  	Malformed UTF-8 character (unexpected end of string)
>  
>  errors in a function that's dealing only with strings that are read from
>  a file that was written to a file, and is being read back using the
>  :utf8 encoding layer. I had thought that substr was always safe on such
>  strings, but it's starting to look like that was a vain hope....

The :utf8 layer just slaps on the UTF8 flag trusting the data it reads
to be well formed utf8.

You can use the :encoding(UTF-8) layer if you don't trust the file
content to be valid UTF8, and then set $PerlIO::encoding::fallback to
specify what to do with bad sequences.

Regards,
Gisle