Python 从subprocess运行的子进程中实时获取输出的例子

import sys
import time
 
 
for i in range(5):
  sys.stdout.write('Processing {}\n'.format(i))
  time.sleep(1)
 
for i in range(5):
  sys.stderr.write('Error {}\n'.format(i))
  time.sleep(1)

import shlex
import subprocess
 
if __name__ == '__main__':
  shell_cmd = 'python3 subprogram.py'
  cmd = shlex.split(shell_cmd)
  p = subprocess.Popen(cmd, shell=False, stdout=subprocess.PIPE, stderr=subprocess.STDOUT)
  while p.poll() is None:
    line = p.stdout.readline()
    line = line.strip()
    if line:
      print('Subprogram output: [{}]'.format(line))
  if p.returncode == 0:
    print('Subprogram success')
  else:
    print('Subprogram failed')

import sys
import time
 
 
for i in range(5):
  sys.stdout.write('Processing {}\n'.format(i))
  sys.stdout.flush()
  time.sleep(1)
 
for i in range(5):
  sys.stderr.write('Error {}\n'.format(i))
  sys.stderr.flush()
  time.sleep(1)