read() # when reading from a file, or
unpack() # using b or B in the template when reading from a string

##</code><code>##

$a = $b << 3;

##</code><code>##

$a = $b >> 2;

##</code><code>##

$c = $a & $b;

##</code><code>##

$c = $a | $b;

##</code><code>##

$c = $a ^ $b;

##</code><code>##

$hex =~ s/([01]{4})/sprintf("%.1x", eval('0b'.$binary))/eg;