This is a thin wrapper around the shellwords.pl package, which comes
preinstalled with Perl.  This module imports a single subroutine,
shellwords().  The shellwords() routine parses lines of text and
returns a set of tokens using the same rules that the Unix shell does
for its command-line arguments.  Tokens are separated by whitespace,
and can be delimited by single or double quotes.  The module also
respects backslash escapes.