I'm a litte bit confused about the interaction between Term::Readkey and waitpid. I hope someone can make me understand what's going on here.

so here's my problem:
There's a program running in a child process which is controlled by the parent waiting for a keystroke or waiting for the child to terminate. I've set the ReadMode to raw.
this code works:

    while ( (not defined ($key = ReadKey (-1))) && ($dead != -1) ) {
        $dead = waitpid(-1,&WNOHANG);
    }
[download]

$dead returns -1 if the child terminates

but this one fails:

    while ( (not defined ($key = ReadKey (0))) && ($dead != -1) ) {
        $dead = waitpid(-1,&WNOHANG);
    }
[download]

$dead returns 0 even if the child terminates

I don't want to use the first code-snipplet because my CPU usage increases up to 80% :(

tnx for any comment

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