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bytes(3)





NAME

       bytes - Perl pragma to force byte semantics rather than character
       semantics


SYNOPSIS

           use bytes;
           no bytes;


DESCRIPTION

       The "use bytes" pragma disables character semantics for the rest of the
       lexical scope in which it appears.  "no bytes" can be used to reverse
       the effect of "use bytes" within the current lexical scope.

       Perl normally assumes character semantics in the presence of character
       data (i.e. data that has come from a source that has been marked as
       being of a particular character encoding). When "use bytes" is in
       effect, the encoding is temporarily ignored, and each string is treated
       as a series of bytes.

       As an example, when Perl sees "$x = chr(400)", it encodes the character
       in UTF-8 and stores it in $x. Then it is marked as character data, so,
       for instance, "length $x" returns 1. However, in the scope of the
       "bytes" pragma, $x is treated as a series of bytes - the bytes that
       make up the UTF8 encoding - and "length $x" returns 2:

           $x = chr(400);
           print "Length is ", length $x, "\n";     # "Length is 1"
           printf "Contents are %vd\n", $x;         # "Contents are 400"
           {
               use bytes;
               print "Length is ", length $x, "\n"; # "Length is 2"
               printf "Contents are %vd\n", $x;     # "Contents are 198.144"
           }

       For more on the implications and differences between character seman-
       tics and byte semantics, see perlunicode.


SEE ALSO

       perlunicode, utf8

perl v5.8.0                       2002-06-01                          bytes(3)

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