当它完成时，popen . communication将设置returncode属性(*)。以下是相关文档部分:

Popen.returncode 
  The child return code, set by poll() and wait() (and indirectly by communicate()). 
  A None value indicates that the process hasn’t terminated yet.

  A negative value -N indicates that the child was terminated by signal N (Unix only).

所以你可以这样做(我没有测试它，但它应该工作):

import subprocess as sp
child = sp.Popen(openRTSP + opts.split(), stdout=sp.PIPE)
streamdata = child.communicate()[0]
rc = child.returncode

(*)发生这种情况是因为它的实现方式:在设置线程来读取子流之后，它只调用wait。

只是指出一个常见的误解，你应该尽量避免Popen。引用文档，

推荐的方法 调用子流程是 使用run()函数 对于所有用例 它可以处理。 更高级的 用例，底层 Popen接口 可直接使用。

如果你只是想运行一个子进程并等待它完成，那就是使用subprocess.run或它的遗留兄弟子进程的一行代码。调用和子流程。你不需要复制/粘贴和/或理解围绕底层Popen对象所需的通信和等待等方法的复杂性。

import subprocess

proc = subprocess.run(
    [openRTSP] + opts.split(),
    capture_output=True,
    # avoid having to explicitly encode
    text=True)
data = proc.stdout
result = proc.returncode

如果不想从流程中捕获输出，可以将capture_output=True替换为stdout=subprocess。DEVNULL(可能与stderr类似);如果两者都不存在，则输出将简单地显示给用户，超出Python的控制范围。

此外，除非你在opts中的选项完全是微不足道的，否则通常用shlex.split()替换常规字符串split()，它理解如何处理带引号的字符串。

这对我很管用。它还打印子进程返回的输出

child = subprocess.Popen(serial_script_cmd, shell=True, stdout=subprocess.PIPE, stderr=subprocess.STDOUT)
    retValRunJobsSerialScript = 0
    for line in child.stdout.readlines():
        child.wait()
        print line           
    retValRunJobsSerialScript= child.returncode

请看评论。

代码:

import subprocess


class MyLibrary(object):

    def execute(self, cmd):
        return subprocess.Popen(cmd, stdout=subprocess.PIPE, stderr=subprocess.STDOUT, universal_newlines=True,)
      
    def list(self):
        command = ["ping", "google.com"]
        sp = self.execute(command)
        status = sp.wait()  # will wait for sp to finish
        out, err = sp.communicate()
        print(out)
        return status # 0 is success else error


test = MyLibrary()

print(test.list())

输出:

C:\Users\shita\Documents\Tech\Python>python t5.py

Pinging google.com [142.250.64.78] with 32 bytes of data:
Reply from 142.250.64.78: bytes=32 time=108ms TTL=116
Reply from 142.250.64.78: bytes=32 time=224ms TTL=116
Reply from 142.250.64.78: bytes=32 time=84ms TTL=116
Reply from 142.250.64.78: bytes=32 time=139ms TTL=116

Ping statistics for 142.250.64.78:
    Packets: Sent = 4, Received = 4, Lost = 0 (0% loss),
Approximate round trip times in milli-seconds:
    Minimum = 84ms, Maximum = 224ms, Average = 138ms

0

Exitcode = data.wait()。如果子进程写入标准输出/错误，和/或从标准输入读取，并且没有对等点，则子进程将被阻塞。

在调用process. communication()之后使用process.wait()。 例如:

import subprocess

process = subprocess.Popen(['ipconfig', '/all'], stderr=subprocess.PIPE, stdout=subprocess.PIPE)
stdout, stderr = process.communicate()
exit_code = process.wait()
print(stdout, stderr, exit_code)