You are missing the sigil at "counter <10". You would have spotted this if you used strict; 
use strict;
my $counter=0;

print"TOP\n";

while( $counter++<10)
{
    last if eof(STDIN);

    $_=<>;
    print "$counter $_";
}
print "BOTTOM";

[download]
Update:

More caveats:
The second part of your conditional will never be checked because the first part is always true, unless the end of the file is reached.
Furthermore it seems the <> does not assign the read line to $_ when there is a && afterwards.
I don't know why. Anyone can explain that?

Update: Silliness striked. Thanks Roy_Johnson.


holli, /regexed monk/

In reply to Re: peeling the top 10 lines from a file by holli
in thread peeling the top 10 lines from a file by jjohhn

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