FAQ 4.70 How do I handle binary data correctly?

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4.70: How do I handle binary data correctly?

    Perl is binary clean, so this shouldn't be a problem. For example, this
    works fine (assuming the files are found):

        if (`cat /vmunix` =~ /gzip/) {
            print "Your kernel is GNU-zip enabled!\n";

    On less elegant (read: Byzantine) systems, however, you have to play
    tedious games with "text" versus "binary" files. See "binmode" in
    perlfunc or perlopentut.

    If you're concerned about 8-bit ASCII data, then see perllocale.

    If you want to deal with multibyte characters, however, there are some
    gotchas. See the section on Regular Expressions.


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