I am looking for a way to process data using some small command-line utilities that each do 1 thing. (I run under windows).

I have a variable, @data, containing, well data ;)

I want to pass it to the first program, read the results. Then I want to pass the results to the second program and read the final answer. (it would be ideal to get to munge the @data between calling prog1 and prog2)

Kinda like: @ans = `getnames | sort`

But, I want to pass @data to getnames (which will do some work) and then have the results goto sort (which will do more work), then back in my Perl program.

One option might be to use 1 or more temporary files:
write @data to temp1.dat
execute `type temp1.dat | getnames > temp2.dat`
(would be ideal to muncge @data here...) execute `type temp2.dat | sort > temp3.dat`
@ans = `type temp3.dat`

I had originally thought stdin and maybe Open2 would work, but, 'kwoff' pointed out that Open2, will block for programs like "sort".

I do have access to the "c" source of the utilites. So I could go in and make sure that I read all stdin and close it before I try to write to stdout. (I think it does this already...from what I can tell ;-)

One cool thing about Unix is all of those small utilities that you can combine into powerfull functions...I hope to emulate this, instead of using temp files that need to be cleaned up...

This might be hard or easy, but please don't assume, I know what I am doing ;-) and thanks for any ideas

In reply to calling mult files by smackdab

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