$ cat ps_info.pl
#!/usr/bin/perl
@a = ( "one", "two", "three", "four", "five" );
for (1..50)
{
    print $0 . "," .$a[$c%5]."\n";
    $0 = $a[$c%5];
    $c++;
    sleep 2;
}
exit;

##</code><code>##

$ ./ps_info.pl
./ps_info.pl,one
one,two
two,three
three,four
four,five
five,one
one,two
two,three
three,four
four,five
five,one
one,two
two,three

##</code><code>##

 5578 pts/5    S      0:00 /usr/bin/perl ./ps_info.pl