what does perl operator “||=” do?

Question

What does the operator ||= do in perl?

to be more specific if you have a code like:

my ($my_link);
$my_link  ||= DownloadF($file,\'l\') if          


        

Answer 1

It assigns only if variable evaluates to false value. In each of your example lines, $my_link will only be assigned if the condition $s->{..} is true.