Make sure your arguments are numbers, not strings: 
    print  161  &  255;   # Prints 161
    print "161" & "255";  # Prints 041

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You probably use variables, so you have to make sure Perl thinks they contain only numbers, and not strings. If you populate your variables by reading it from file, or by extracting it with a regex, Perl thinks the variables are strings. You can numify them by adding 0s: 
    print +("161" + 0) & ("255" + 0);  # Prints 161

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In reply to Re: bitwise operators by Anonymous Monk
in thread bitwise operators by gtdunlap

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