Hi there!

I have some trouble understanding how to redirect input from one pipe to another. Here is what I want to do:

I open one command and process its output in a while loop. On some condition I open another command inside this while loop and I want its output to appear in the same pipe as the output of the first command.

Ok, here's some pseudo-code to make things a bit more clear:

open INPUT, "some_script |";
while (<INPUT>) {
    if ($some_condition) {
        open ">&INPUT", "some_other_script |";
    }
    do_something_with_input();
}

[download]

(I know there are missing close and or die statements.) Both scripts run over some period of time and give progress information (like 50% done) as their output, so it's important to monitor output from both scripts simultaneously.

Any ideas? Is this possible?

Thanks alot for your help!

In reply to Merging two pipes by cmburns

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