Added threading.py

* Will be used by hw_diags.py and ddrescue.py for
  * Better control over badblocks
  * Background the tmux pane fixes

.bin/Scripts/functions/threading.py

@@ -0,0 +1,47 @@
+# Wizard Kit: Functions - Threading
+
+from threading import Thread
+from queue import Queue, Empty
+
+# Classes
+class NonBlockingStreamReader():
+  """Class to allow non-blocking reads from a stream."""
+  # Credits:
+  ## https://gist.github.com/EyalAr/7915597
+  ## https://stackoverflow.com/a/4896288
+
+  def __init__(self, stream):
+    self.stream = stream
+    self.queue = Queue()
+
+    def populate_queue(stream, queue):
+      """Collect lines from stream and put them in queue."""
+      while True:
+        line = stream.read(1)
+        if line:
+          queue.put(line)
+
+    self.thread = start_thread(
+      populate_queue,
+      args=(self.stream, self.queue))
+
+  def read(self, timeout=None):
+    try:
+      return self.queue.get(block = timeout is not None,
+          timeout = timeout)
+    except Empty:
+      return None
+
+
+# Functions
+def start_thread(function, args=[], daemon=True):
+  """Run function as thread in background, returns Thread object."""
+  thread = Thread(target=function, args=args, daemon=daemon)
+  thread.start()
+  return thread
+
+
+if __name__ == '__main__':
+  print("This file is not meant to be called directly.")
+
+# vim: sts=2 sw=2 ts=2