If I look at the ascii table

then you only see a part of the non-printable characters available on modern computer systems. Unicode has more control characters, emoji skin tone modifiers, right-to-left mark and a host of other stuff that is unprintable on it's own.

As an additional bonus, the same character on screen can sometimes be encoded in Unicode in multiple ways, see Unicode equivalence.

Unfortunately, input processing has gotten a tad more complex since the world gave up on ye olde ASCII table. On the bright side, these days more than the 20% of world population of the old ASCII days can now type their name into a computer with a reasonable expectation that it will be processed correctly.

perl -e 'use Crypt::Digest::SHA256 qw[sha256_hex]; print substr(sha256_hex("the Answer To Life, The Universe And Everything"), 6, 2), "\n";'

In reply to Re^3: Capture a non-printable char and test what it is by cavac
in thread Capture a non-printable char and test what it is by almsdealer

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