获取Python中所有正在运行的进程的STDOUT，STDERR

Question

I'm a Python noob.

Is there a way to get the STDOUT and STDERR of all running processes in Python? Some processes exit after a long time and their status is constantly being written to STDOUT.

Answer 1

To get subprocess output line by line without waiting for it to close:

p = subprocess.Popen(cmd, stdout=subprocess.PIPE, stderr=subprocess.STDOUT, shell=True)
while True:
    o = p.stdout.readline()
    if not o:
        break
    print o

you can use p.stdout.read(n) if want to read every 'n' characters from the process.

Hope this helps.