python - Popen.communicate() 返回 (None, None) 即使脚本打印结果

Question

我对 Popen.communicate() 有疑问。

我有返回字符串的脚本。

然后我编写了第二个脚本来获取该变量。

v = "./myscript arg1 arg2"
com = subprocess.Popen(v, shell=True).communicate()
print com

com 返回(无，无)。关键是我可以先在脚本中打印结果， shell 打印结果也是如此。我不能只将该打印分配给变量。

当然第一个脚本返回值，而不是打印它。

Answer 1

来自docs :

Note that if you want to send data to the process’s stdin, you need to create the Popen object with stdin=PIPE. Similarly, to get anything other than None in the result tuple, you need to give stdout=PIPE and/or stderr=PIPE too.

因此，创建 Popen 对象:

subprocess.Popen("./myscript arg1 arg2", shell=True,
                 stdout=subprocess.PIPE, stderr=subprocess.PIPE)