您是对的-没有很好的API。您也说对了第二点-设计一个使用线程为您执行此操作的函数非常容易。

import threading
import subprocess

def popen_and_call(on_exit, popen_args):
    """
    Runs the given args in a subprocess.Popen, and then calls the function
    on_exit when the subprocess completes.
    on_exit is a callable object, and popen_args is a list/tuple of args that 
    would give to subprocess.Popen.
    """
    def run_in_thread(on_exit, popen_args):
        proc = subprocess.Popen(*popen_args)
        proc.wait()
        on_exit()
        return
    thread = threading.Thread(target=run_in_thread, args=(on_exit, popen_args))
    thread.start()
    # returns immediately after the thread starts
    return thread

甚至线程在Python中都非常容易，但是请注意，如果on_exit（）的计算量很大，则需要将其放在单独的进程中，而不是使用多处理（这样GIL不会降低程序速度）。这实际上非常简单-
您基本上可以将所有调用替换为threading.Thread，multiprocessing.Process因为它们遵循（几乎）相同的API。