http://www.perlmonks.org?node_id=1221773

edwyr has asked for the wisdom of the Perl Monks concerning the following question:

I've started reading _Higher-Order Perl_ and read a command I'm not familiar with. Normally I would use perldoc or perldoc -f, but the regex is "painful" on this one...

The line is: my $total = -s $top; What is the = -s? Mike