Process output of one script with another script.

tphyahoo has asked for the wisdom of the Perl Monks concerning the following question:

Monks, I'm in the dos shell with ActiveState perl.

oneTwoThree.pl prints

one
two
three
[download]

filterTwoThree.pl checks lines of input and only prints if they match "two" or "three. I want to run something like

filterTwoThree.pl | oneTwoThree.pl
[download]

and have this spit out

two 
three
[download]

Is there a way I can hook these scripts up in one line of dos? I have never used pipes before but I am beginning to see how they could be useful. I think this might be easier in the unix shell... is it worth installing Cygwin so I can use pipes?

Thanks for your wisdom!

#!c:/perl/bin/perl
#oneTwoThree.pl
use warnings;
use strict;

print "one\n";
print "two\n";
print "three\n";
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#filterTwoAndThree.pl
use warnings;
use strict;

if (/two|three/) {
  print $_;
}
[download]

UPDATE: Maybe the answer is here: How do I store and manipulate the output from another process?

UPDATE: Thanks RazorbladeBidet. I googled around and found many places that suggested dos pipes were somehow handicapped, but in this case I can get what I want to work with, by adding the -n flag

perl oneTwoThree.pl | perl -n filterTwoAndThree.pl
[download]

Comment on Process output of one script with another script. Select or Download Code

Replies are listed 'Best First'.
Re: Process output of one script with another script. by maard (Pilgrim) on Feb 18, 2005 at 18:53 UTC
So what keeps you from trying if it works or not? just say `oneTwoThree.pl \| filterTwoThree.pl` [download] instead of `filterTwoThree.pl \| oneTwoThree.pl` [download] Pipes worked well on DOS from it's earliest versions. But your question isn't related to perl, don't you think? ;)	[reply] [d/l] [select]
Re^2: Process output of one script with another script. by dave_the_m (Monsignor) on Feb 18, 2005 at 20:34 UTC
Pipes worked well on DOS from it's earliest versions although strictly speaking, in early versions of DOS, pipes were just syntactic sugar: `foo \| more is implemented as foo > tmpfile; more < tmpfile; del tmpfile` [download] which fails utterly in the face of a command that produces infinite output. I don't know whether things have improved since; I certainly hope so, but I haven't used MS on the desktop since 1987. Dave.	[reply] [d/l]
Re: Process output of one script with another script. by RazorbladeBidet (Friar) on Feb 18, 2005 at 18:54 UTC
DOS has pipes, so you won't have any problems. But you have it reversed, you want `oneTwoThree.pl \| filterTwoAndThree.pl` You basically just want to read the input from STDIN. See perlop for more info -------------- It's sad that a family can be torn apart by such a such a simple thing as a pack of wild dogs	[reply] [d/l]