Pipe stdout of first command to a second command about kommand HOT 2 CLOSED

fun pipeTest() {
    val child1 = Command("zsh")
        .args("-c", "unset count; count=0; while ((count < 10)) do ((count += 1));echo from child1:${"$"}count;done")
        .stdout(Stdio.Pipe)
        .spawn()
    val child2 = Command("zsh")
        .args("-c", "while read line; do echo from child2:${"$"}line; done")
        .stdin(Stdio.Pipe)
        .stdout(Stdio.Inherit)
        .spawn()
    val child1StdoutReader = child1.getChildStdout()!!
    val child2StdinWriter = child2.getChildStdin()!!
    // child1's output flows to child2's input
    child1StdoutReader.lines().forEach {
        child2StdinWriter.appendLine(it)
    }
    child2StdinWriter.close()
}