Greetings my Brothers,

I'd like to create two child processes, pipe the first one's STDOUT into the second one's STDIN, and read the first one's STDERR. After reading the pipe manpage and perlipc I came up with this (broken) piece of code :

my ($READ, $WRITE);
pipe ($READ, $WRITE);

my $child1 = fork ();
unless ($child1) {
    *STDOUT = $WRITE;
    exec ('cat', $0);
}

my $child2 = fork ();
unless ($child2) {
    *STDIN = $READ;
    exec ('grep', 'grep');
}

waitpid ($child1, 0);
waitpid ($child2, 0);

[download]

I think my error is in the assignments to STDIN and STDOUT. I don't fully understand globs, so what you see here is mainly guesswork. I think what I need is some sort of equivalement to the C system call dup2. Any thoughts?

thank you for your time
MT

In reply to Pipe two child processes by MediaTracker

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