use warnings;
use strict;

my $str = "abc";
my $last_pos =0;
while ($str =~ m/.|$/gc) {
   my $curr_pos = pos($str);
   printf("1: %d", $curr_pos);
   ($curr_pos == $last_pos) ? print "  EOString\n" : print "\n";
   $last_pos = $curr_pos;
}
__END__
1: 1
1: 2
1: 3
1: 3  EOString