如何修复这个 bash 脚本？答案

【问题标题】：How to fix this bash script?如何修复这个 bash 脚本？
【发布时间】：2021-07-17 18:31:51
【问题描述】：

我这里有这个脚本：

killall -q $1
#turns out system already has a method for this, yey
#-q because we already have a error handling
returned=$?
#does this so that it doesn't read the success state of the ifs
if [ $returned = 0 ]
then 
    printf "Process kill attempt returned "
    echo $returned
    echo "Process killed sucessfully."
    #yey we did it
else
    #oh noes it failed
    printf "Process kill attempt returned "
    echo $returned
    echo "Process kill attempt failed."
    printf "Most likely cause of failure: "
    if [ $returned = 1 ]
    then
        echo "process does not exist or is not running"
    elif [ $returned = 2 ]
        echo "process is system task; insufficient permissions"
    else
        echo "unknown failure " $returned "; no known fail in database has this value"
    fi
fi

查看时没发现问题，但运行时出现此错误。

nathan@HAL-LINUX:~$ xscreensaver
nathan@HAL-LINUX:~$ killproc xscreensaver
/usr/local/bin/killproc: line 23: syntax error near unexpected token `else'
/usr/local/bin/killproc: line 23: ` else'
nathan@HAL-LINUX:~$

我的原始脚本省略了嵌套的 if，只是直接告诉您它因错误 3、1 或 2 而失败。

我应该回去吗？或者有没有办法解决这个问题？

【问题讨论】：

shellcheck.net 会发现问题的。
@Socowi：老实说，我什至没有阅读代码。我刚刚对其运行了 shellcheck，它告诉我错误是什么：D

标签： bash if-statement nested sh nested-if

【解决方案1】：

您在elif 之后忘记了then：

if [ $returned = 1 ]
    then
        echo "process does not exist or is not running"
    elif [ $returned = 2 ]
    then
        echo "process is system task; insufficient permissions"
    else
        echo "unknown failure " $returned "; no known fail in database has this value"
    fi

【讨论】：