I want to print the first 3 lines of a file. This works: 
my $f = "/etc/fstab";
open ( my $fh, "<", $f );

while ( <$fh> ) {
    print if (1..3) ;
}

[download]
But if I print everything, rewind the file to the beginning, and print the first three lines again, it does not work: 
my $f = "/etc/fstab";
open ( my $fh, "<", $f );

while ( <$fh> ) {
    chomp;
    print "$_\n";
}

print "=" x 78, "\n\n";
print "after 1st while loop\n";

seek( $fh, 0, 0);

while ( <$fh> ) {
    print if (1..3) ;
}

[download]
using warnings, strict, autodie (implicit in the code).

I can solve it using a counter inside the latest while loop, but I am just curious why it does not work as expected. Thanks for any insights.

In reply to seek question by natxo

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