Perl will assume bytes

Don't assume this. :-)

Perl 5.8.0 will "honor" your TERM environment variable and may use UTF-8 for IO if your terminal is UTF-8.

For the original problem: Use :bytes when opening the IO channel and treat the content as bytes. If, and only if, you need to work with some Unicode (or UTF-8 or whatever codepage) text convert a substring of it. So the scalar will be marked as containing bytes and substr will work on 8 bit wide characters == bytes. If you let Perl decide if the stream is bytes or UTF-8 it will fail (die/warn/data corruption) if Perl decides for UTF-8 and gets a JPG image...

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In reply to Re: Re: Re: Re: How do I safely, portably extract one or more bytes from a string? by Beechbone
in thread How do I safely, portably extract one or more bytes from a string? by Anonymous Monk

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