substr $var, 1 returns the string in $var minus the first character. That's what converts the 8 character binary output from unpack into the desired 7 character one. You could do the same thing with a substitution with the /r modifier, and I'm sure a number of other methods. In the OP, it's handled with s/^.//;, but then you can't chain.
#11929 First ask yourself `How would I do this without a computer?' Then have the computer do it the same way.
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