$counter is mis-typed within your while expression. It's missing its '$' sigil. Also, I think that some of the magic of while(<>) is lost when you put other criteria within the while() criteria.

You could do it like this...

print "TOP\n";
while( <> ) {
    last if $. > 10; # $. is the current line number within the file.
    print "$_\n";
}
print "BOTTOM\n";
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