我正在编写一个python脚本,启动几个进程和数据库连接。有时我想用Ctrl+C信号终止脚本,我想做一些清理工作。

在Perl中,我会这样做:

$SIG{'INT'} = 'exit_gracefully';

sub exit_gracefully {
    print "Caught ^C \n";
    exit (0);
}

如何在Python中进行类似操作?


当前回答

另一个片段

将main作为main函数,将exit_elegant作为Ctrl+C处理程序

if __name__ == '__main__':
    try:
        main()
    except KeyboardInterrupt:
        pass
    finally:
        exit_gracefully()

其他回答

另一个片段

将main作为main函数,将exit_elegant作为Ctrl+C处理程序

if __name__ == '__main__':
    try:
        main()
    except KeyboardInterrupt:
        pass
    finally:
        exit_gracefully()

来自Python的文档:

import signal
import time

def handler(signum, frame):
    print 'Here you go'

signal.signal(signal.SIGINT, handler)

time.sleep(10) # Press Ctrl+c here

我调整了@udi的代码来支持多个信号(没什么特别的):

class GracefulInterruptHandler(object):
    def __init__(self, signals=(signal.SIGINT, signal.SIGTERM)):
        self.signals = signals
        self.original_handlers = {}

    def __enter__(self):
        self.interrupted = False
        self.released = False

        for sig in self.signals:
            self.original_handlers[sig] = signal.getsignal(sig)
            signal.signal(sig, self.handler)

        return self

    def handler(self, signum, frame):
        self.release()
        self.interrupted = True

    def __exit__(self, type, value, tb):
        self.release()

    def release(self):
        if self.released:
            return False

        for sig in self.signals:
            signal.signal(sig, self.original_handlers[sig])

        self.released = True
        return True

这段代码支持键盘中断调用(SIGINT)和SIGTERM (kill <process>)

如果你想确保你的清理过程完成,我将通过使用SIG_IGN添加到Matt J的答案,这样进一步的SIGINT将被忽略,这将防止你的清理被打断。

import signal
import sys

def signal_handler(signum, frame):
    signal.signal(signum, signal.SIG_IGN) # ignore additional signals
    cleanup() # give your process a chance to clean up
    sys.exit(0)

signal.signal(signal.SIGINT, signal_handler) # register the signal with the signal handler first
do_stuff()

您可以使用Python内置信号模块中的函数来设置Python中的信号处理程序。特别是信号。Signal (signalnum, handler)函数用于为信号signalnum注册处理函数。