Bash，评估中的CTRL + C不会中断主脚本 [英] Bash, CTRL+C in eval not interrupting the main script

问题描述

在我的bash脚本中，我正在运行一个存储在 $ cmd 变量中的外部命令.(可以是任何东西，甚至可以是一些简单的bash oneliner.)

In my bash script, I'm running an external command that's stored in $cmd variable. (It could be anything, even some simple bash oneliner.)

如果在运行脚本时按下 ctrl + C ，我希望它杀死当前正在运行的 $ cmd ，但仍应继续运行主脚本.但是，我想保留在运行主脚本时使用 ctrl + C 杀死主脚本的选项.

If ctrl+C is pressed while running the script, I want it to kill the currently running $cmd but it should still continue running the main script. However, I would like to preserve the option to kill the main script with ctrl+C when the main script is running.

#!/bin/bash
cmd='read -p "Ooook?" something; echo $something; sleep 4 ' 
while true; do
    echo "running cmd.."
    eval "$cmd"     # ctrl-C now should terminate the eval and print "done cmd"
    echo "done cmd"
    sleep 5         # ctrl-C now should terminate the main script
done

有人知道如何以一种不错的bash方式进行操作吗?

Any idea how to do it some nice bash way?

根据答案应用的更改:

#! /bin/bash

cmd='read -p "Ooook1?" something; read -p "Oook2?" ; echo $something; sleep 4 ' 
while true; do
    echo "running cmd.."
    trap "echo Interrupted" INT
    eval "($cmd)"     # ctrl-C now should terminate the eval and print "done cmd"
    trap - INT
    echo "done cmd"
    sleep 5         # ctrl-C now should terminate the main script
done

现在，在"Ooook1?"时按 ctrl + C .只有完成读取后，读取才会中断评估.(它将在"Oook2"之前中断.)但是，它将立即中断"sleep 4".

Now, pressing ctrl+C while "Ooook1?" read will break the eval only after that read is done. (it will interrupt just before "Oook2") However it will interrupt "sleep 4" instantly.

在这两种情况下，它都将做正确的事情-它将中断eval子外壳，所以我们快到了-只是那种奇怪的读取行为.

In both cases it will do the right thing - it will just interrupt the eval subshell, so we're almost there - just that weird read behaviour..

推荐答案

如果您有能力在子shell中运行 eval 部分，那么您要做的全部"就是捕获SIGINT.

If you can afford having the eval part run in a subshell, "all" you need to do is trap SIGINT.

#! /bin/bash

cmd='read -p "Ooook1?" something; read -p "Oook2?" ; echo $something; sleep 4 ' 
while true; do
    echo "running cmd.."
    trap "echo Interrupted" INT
    eval "($cmd)"     # ctrl-C now should terminate the eval and print "done cmd"
    trap - INT
    echo "done cmd"
    sleep 5         # ctrl-C now should terminate the main script
done

虽然不知道这是否适合您的特定需求.

Don't know if that will fit your specific need though.

$ ./t.sh 
running cmd..
Ooook1?^CInterrupted
done cmd
^C
$ ./t.sh 
running cmd..
Ooook1?qsdqs^CInterrupted
done cmd
^C
$ ./t.sh 
running cmd..
Ooook1?qsd
Oook2?^CInterrupted
done cmd
^C
$ 
GNU bash, version 4.1.9(2)-release (x86_64-pc-linux-gnu)

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