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?
当前回答
这是我的解决方案，我使用线程和事件:
import subprocess
from threading import Thread, Event
def kill_on_timeout(done, timeout, proc):
if not done.wait(timeout):
proc.kill()
def exec_command(command, timeout):
done = Event()
proc = subprocess.Popen(command, stdout=subprocess.PIPE, stderr=subprocess.PIPE)
watcher = Thread(target=kill_on_timeout, args=(done, timeout, proc))
watcher.daemon = True
watcher.start()
data, stderr = proc.communicate()
done.set()
return data, stderr, proc.returncode
在行动:
In [2]: exec_command(['sleep', '10'], 5)
Out[2]: ('', '', -9)
In [3]: exec_command(['sleep', '10'], 11)
Out[3]: ('', '', 0)
其他回答
我已经在Windows, Linux和Mac上成功地使用了killableprocess。如果你使用Cygwin Python，你将需要OSAF的killableprocess版本，否则本机Windows进程将不会被杀死。
python 2.7
import time
import subprocess
def run_command(cmd, timeout=0):
start_time = time.time()
df = subprocess.Popen(cmd, stdout=subprocess.PIPE, stderr=subprocess.PIPE)
while timeout and df.poll() == None:
if time.time()-start_time >= timeout:
df.kill()
return -1, ""
output = '\n'.join(df.communicate()).strip()
return df.returncode, output
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()
仅适用于Linux，但如果有人想使用subprocess.getstatusoutput()，其中timeout参数不可用，您可以在命令的开头使用内置的Linux timeout，即:
import subprocess
timeout = 25 # seconds
cmd = f"timeout --preserve-status --foreground {timeout} ping duckgo.com"
exit_c, out = subprocess.getstatusoutput(cmd)
if (exit_c == 0):
print("success")
else:
print("Error: ", out)
超时参数:
——preserve-status:保留退出状态 ——前台:在前台运行 25:超时时间，单位为秒
在Python 3.7.8中超时测试后捕获的输出示例:
try:
return subprocess.run(command, shell=True, capture_output=True, timeout=20, cwd=cwd, universal_newlines=True)
except subprocess.TimeoutExpired as e:
print(e.output.decode(encoding="utf-8", errors="ignore"))
assert False;
异常子进程。TimeoutExpired有输出和其他成员:
cmd -用于生成子进程的命令。 timeout -超时时间，单位为秒。 output -子进程的输出，如果它是由run()或 check_output()。否则,没有。 stdout -输出的别名，用于与stderr对称。 stderr -子进程的stderr输出，如果它被捕获 run()。否则,没有。
更多信息:https://docs.python.org/3/library/subprocess.html#subprocess.TimeoutExpired
