Perl in a Nutshell, 2nd Edition

Shell

Allows you to invoke Unix shell utilities as if they were Perl subroutines. Arguments (including switches) are passed to the utilities as strings:

use Shell qw(date cp ps);  # List shell commands you want to use

$date = date(  );   # Put the output of the date(1) command into $date
cp("-p" "/etc/passwd", "/tmp/passwd");  # Copy password file to a tmp file
print ps("-ww");  # Print the results of a "ps -ww" command