You'll need to open the file first. eg:

open my $in, '<', 'file.txt' or die "Cannot open file for reading: $!"
+;
print sort { ($a =~ /\S+\n$/g)[0] cmp ($b =~ /\S+\n$/g)[0] } <$in>;
close $in;

[download]

See open and close for all the details.

In reply to Re^3: Sort alphabetically from file by hippo
in thread Sort alphabetically from file by edujs7

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