You are combining multi-process models, which is generally problematic. After creating a thread, you create a pipe, fork, redirect i/o and then call system, which forks again. When that second fork gets called, it seems that it is twinning the STDOUT (I assume you don't care about STDERR since you never redirect) from the main thread rather than your threaded-then-forked line of control. Why are you trying to use threads when you already have a functional code using forks and pipes? You can certain use something like the following code in place of that threading:

my $pid = fork();
if ($pid == 0) {
    print "Hello!\n";
} else {
    execute();
}

[download]

Another possibility is to modify your "can't modify" routine to use backticks in place of system and print the output yourself.

In reply to Re: Redirecting stdout with threads by kennethk
in thread Redirecting stdout with threads by michi

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