readdir returns such files as '.' and '..'

opendir my $dir, './var';
say join "\n", readdir $dir;
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Output:

fonts.tar.gz
.
c
..
[download]

Reading this stuff yields nothing:

open my $file, '<', '.';
my @lines = <$file>;
say join "\n", @lines;
say scalar @lines;
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Produces empty line and 0.

Use glob instead...