unlink "a", "b", "c";     # valid
    unlink "a b c";           # invalid

##</code><code>##

...
use CGI;

my $form = CGI->new();

if ( $form->param('action'} eq "delete" ) {
   my @files_to_delete = $form->param('chosen_files');
   unlink join ",", @files_to_delete;
}
...

##</code><code>##

   print $f{'file'};