chop($line);              # Best way. Removes the last character.
$line =~ s/.\z//s;        # Works, but not as simple as 'chop': substitution.
substr($line, -1,1,'');   # Works, but not as simple as 'chop': substr with empty-string replacement.
substr($line,-1,1) = '';  # Works, but not as simple as 'chop': substr as an lvalue.