下面是运行任意命令返回其标准输出数据的Python代码,或在非零退出码上引发异常:
proc = subprocess.Popen(
cmd,
stderr=subprocess.STDOUT, # Merge stdout and stderr
stdout=subprocess.PIPE,
shell=True)
communication用于等待进程退出:
stdoutdata, stderrdata = proc.communicate()
子进程模块不支持超时——杀死运行超过X秒的进程的能力——因此,通信可能需要很长时间才能运行。
在Windows和Linux上运行的Python程序中实现超时的最简单方法是什么?
我有一个问题,我想终止一个多线程子进程,如果它花费的时间超过给定的超时长度。我想在Popen()中设置一个超时,但它不起作用。然后,我意识到Popen().wait()等于call(),所以我有了在.wait(timeout=xxx)方法中设置超时的想法,这最终工作了。因此,我是这样解决的:
import os
import sys
import signal
import subprocess
from multiprocessing import Pool
cores_for_parallelization = 4
timeout_time = 15 # seconds
def main():
jobs = [...YOUR_JOB_LIST...]
with Pool(cores_for_parallelization) as p:
p.map(run_parallel_jobs, jobs)
def run_parallel_jobs(args):
# Define the arguments including the paths
initial_terminal_command = 'C:\\Python34\\python.exe' # Python executable
function_to_start = 'C:\\temp\\xyz.py' # The multithreading script
final_list = [initial_terminal_command, function_to_start]
final_list.extend(args)
# Start the subprocess and determine the process PID
subp = subprocess.Popen(final_list) # starts the process
pid = subp.pid
# Wait until the return code returns from the function by considering the timeout.
# If not, terminate the process.
try:
returncode = subp.wait(timeout=timeout_time) # should be zero if accomplished
except subprocess.TimeoutExpired:
# Distinguish between Linux and Windows and terminate the process if
# the timeout has been expired
if sys.platform == 'linux2':
os.kill(pid, signal.SIGTERM)
elif sys.platform == 'win32':
subp.terminate()
if __name__ == '__main__':
main()
对于python 2.6+,使用gevent
from gevent.subprocess import Popen, PIPE, STDOUT
def call_sys(cmd, timeout):
p= Popen(cmd, shell=True, stdout=PIPE)
output, _ = p.communicate(timeout=timeout)
assert p.returncode == 0, p. returncode
return output
call_sys('./t.sh', 2)
# t.sh example
sleep 5
echo done
exit 1