devarishi:

Here's a trivial example. Suppose you have a program that generates some output, but you'd like the output sorted. You can do it like so:

use strict;
use warnings;
open my $F1, '| sort >t' or die;
while (<DATA>) {
    print $F1 $_;
}
__DATA__
the
quick
red
fox
jumped
over
the
lazy
brown
dog

[download]

This trivial program just writes a few words, and then uses the sort program to sort the output using the sort program as a filter. When you run it, you get this:

$ perl foo.pl
$ cat t
brown
dog
fox
jumped
lazy
over
quick
red
the
the

[download]

...roboticus

When your only tool is a hammer, all problems look like your thumb.

In reply to Re: Filehandles and Input and Output Filters by roboticus
in thread Filehandles and Input and Output Filters by devarishi

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