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
感谢已有的答案，但添加了signal.getsignal()
import signal
# store default handler of signal.SIGINT
default_handler = signal.getsignal(signal.SIGINT)
catch_count = 0
def handler(signum, frame):
global default_handler, catch_count
catch_count += 1
print ('wait:', catch_count)
if catch_count > 3:
# recover handler for signal.SIGINT
signal.signal(signal.SIGINT, default_handler)
print('expecting KeyboardInterrupt')
signal.signal(signal.SIGINT, handler)
print('Press Ctrl+c here')
while True:
pass
其他回答
用signal注册你的处理程序。信号是这样的:
#!/usr/bin/env python
import signal
import sys
def signal_handler(sig, frame):
print('You pressed Ctrl+C!')
sys.exit(0)
signal.signal(signal.SIGINT, signal_handler)
print('Press Ctrl+C')
signal.pause()
代码改编自这里。
更多关于信号的文档可以在这里找到。
你可以通过捕获KeyboardInterrupt异常来处理CTRL+C。您可以在异常处理程序中实现任何清理代码。
感谢已有的答案，但添加了signal.getsignal()
import signal
# store default handler of signal.SIGINT
default_handler = signal.getsignal(signal.SIGINT)
catch_count = 0
def handler(signum, frame):
global default_handler, catch_count
catch_count += 1
print ('wait:', catch_count)
if catch_count > 3:
# recover handler for signal.SIGINT
signal.signal(signal.SIGINT, default_handler)
print('expecting KeyboardInterrupt')
signal.signal(signal.SIGINT, handler)
print('Press Ctrl+c here')
while True:
pass
与Matt J的答案相反，我使用了一个简单的对象。这使我有可能将这个处理程序解析到需要安全停止的所有线程。
class SIGINT_handler():
def __init__(self):
self.SIGINT = False
def signal_handler(self, signal, frame):
print('You pressed Ctrl+C!')
self.SIGINT = True
handler = SIGINT_handler()
signal.signal(signal.SIGINT, handler.signal_handler)
在其他地方
while True:
# task
if handler.SIGINT:
break
你可以像对待其他异常一样对待它(KeyboardInterrupt)。创建一个新文件，并在shell中运行它，包含以下内容，看看我的意思:
import time, sys
x = 1
while True:
try:
print x
time.sleep(.3)
x += 1
except KeyboardInterrupt:
print "Bye"
sys.exit()
