sub copy( source, destination ) {
    open SOURCEFILE "source";
    open DESTINATIONFILE "destination";
    while (<SOURCEFILE>) {
        print DESTINATIONFILE ;
    }
    close DESTINATIONFILE;
    close SOURCEFILE;
}

##</code><code>##

open FILE "<$file";

##</code><code>##

open FILE ">$file";

##</code><code>##

open FILE ">>$file";