如何在 bash 脚本中静默使用 unix kill 命令？
声明：本页面是StackOverFlow热门问题的中英对照翻译，遵循CC BY-SA 4.0协议，如果您需要使用它，必须同样遵循CC BY-SA许可，注明原文地址和作者信息，同时你必须将它归于原作者（不是我）：StackOverFlow
原文地址: http://stackoverflow.com/questions/9402361/
Warning: these are provided under cc-by-sa 4.0 license. You are free to use/share it, But you must attribute it to the original authors (not me):
StackOverFlow
How can you use the unix kill command silently in a bash script?
提问by Jimmy
I'm trying to check if a particular process is running, and if it is, try and kill it.
我正在尝试检查特定进程是否正在运行，如果是，请尝试将其杀死。
I've come up with the following so far:
到目前为止，我提出了以下几点：
PID=$(ps aux | grep myprocessname | grep -v grep | awk '{print }')
if [ -z $PID];
then
echo Still running on PID $PID, attempting to kill..
kill -9 $PID > /dev/null
fi
However when I run this, I get the following output:
但是，当我运行它时，我得到以下输出：
kill: usage: kill [-s sigspec | -n signum | -sigspec] pid | jobspec ... or kill -l [sigspec]
What is the best way to kill a running process on unix silently?
静默杀死 unix 上正在运行的进程的最佳方法是什么？
回答by Mat
[ -z $PID]
is true if $PIDis empty, not the other way around, so your test is inverted.
如果$PID为空，则为真，而不是相反，因此您的测试被反转。
You should be using pgrepif you have that on your system too. (Or even better: pkilland stop worrying about all that shell logic.)
pgrep如果您的系统上也有它，您应该使用它。（或者甚至更好：pkill不要担心所有这些 shell 逻辑。）
回答by John
The answer is easier
The program "killall" is part of almost any distribution.
答案更简单
程序“killall”几乎是任何发行版的一部分。
Examples:
例子：
killall name_of_process &> /dev/null
killall -9 name_of_process &> /dev/null
(( $? == 0)) && echo "kill successful";
Now there also is "pkill" and "pgrep" Example:
现在还有“pkill”和“pgrep”示例：
pkill -9 bash &> /dev/null
(( $? == 0)) && echo "kill successful";
Example:
例子：
for pid in $(pgrep bash); do
kill -9 $pid &> /dev/null
(( $? == 0)) && echo "kill of $pid successful" || echo "kill of $pid failed";
done
And last as you used "ps" in your example, here a better way to use it without the requirement of "grep" "grep -v" and "awk":
最后，当您在示例中使用“ps”时，这里有一种更好的使用方法，无需“grep”、“grep -v”和“awk”：
PIDS="$(ps -a -C myprocessname -o pid= )"
while read pid; do
kill -9 $pid &> /dev/null
((!$?)) && echo -n "killed $pid,";
done <<< "$p"
All those listed methods are better than the long pipe-pipe-pipe imho
所有列出的方法都比长管 - 管 - 管 imho 好
回答by Lars Kotthoff
Try if [ X$PID != X ]in your condition. This is the usual idiom for checking whether a string is empty.
if [ X$PID != X ]在你的情况下尝试。这是检查字符串是否为空的常用习惯用法。
