import os

for pipe_func, name in ((os.pipe, 'os.pipe'), (os.openpty, 'os.openpty')):

    master_fd, slave_fd = pipe_func()

    # Simulate a subprocess writing some data to the
    # slave end of the pipe, and then exiting.
    data = ('%s: success' % name).encode()
    os.write(slave_fd, data)
    os.close(slave_fd)

    gotdata = os.read(master_fd, len(data) + 1) # not enough data
    print(gotdata)
    os.read(master_fd, 1) # one more read => OSError(5)

    os.close(master_fd)