ADDITIONAL SYSTEM INFORMATION :
Ubuntu 21.10 / Debian GNU/Linux 10 (buster)
Java: 17.0.3/11.0.15

A DESCRIPTION OF THE PROBLEM :
When using ProcessBuilder.startPipeline the pipes (or pipe if only 2 ProcessBuilder instance used) created are never closed.

EXPECTED VERSUS ACTUAL BEHAVIOR :
EXPECTED -
the pipes created by ProcessBuilder.startPipeline are closed
ACTUAL -
the pipes created by ProcessBuilder.startPipeline are never closed

---------- BEGIN SOURCE ----------
List<ProcessBuilder> processBuilders = new LinkedList<>();
processBuilders.add(new ProcessBuilder("ls"));
processBuilders.add(new ProcessBuilder("grep", "a"));
List<Process> processes = ProcessBuilder.startPipeline(processBuilders);
Process last = processes.get(processes.size()-1);
last.waitFor();

try (InputStream inputStream = last.getInputStream()) {
    inputStream.readAllBytes();
}
---------- END SOURCE ----------

FREQUENCY : always