Steve, can I ask if you are doing that because we really need to do it in Perl, or just to learn? I mean, those two unix programs are very efficient, so, why not just use them?

Also, you can open shell pipes as if they were files. So, you can easilly do: 

open PIPE, "sort file | uniq -c |";
while(<PIPE>) {
}

[download]

Ok, I know I didn't help you how to write those scripts in Perl, but I hope I made you think if you really need to rewrite those tools in Perl.

Alberto Simões

In reply to Re: perl functionality like unix's "sort -u" and "uniq -c" by ambs
in thread perl functionality like unix's "sort -u" and "uniq -c" by Steve973

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