sel = selectors.DefaultSelector()
sel.register(p.stdout, selectors.EVENT_READ)
sel.register(p.stderr, selectors.EVENT_READ)
sel = selectors.DefaultSelector()
sel.register(p.stdout, selectors.EVENT_READ)
sel.register(p.stderr, selectors.EVENT_READ)
for key, _ in sel.select():
char = key.fileobj.read(1)
if not char:
for key, _ in sel.select():
char = key.fileobj.read(1)
if not char: