Shell脚本编写意外运算符

我已经为这个问题挣扎了几个小时，并尝试了在讨论板上能找到的一切。我无法切换到

bash

，这是在

bin/sh

中

问题在于while循环，

while[$currentID-gt 0]

。错误是

“21:[：2893:意外操作员

#!/bin/sh

Menu_Option=0

echo "WELCOME"
echo "--------------------------------------------------------------"
while [ $Menu_Option -ne 4 ]
do
    echo "select a menu option"
    echo "1- ancestry history"
    echo "2- who is online"
    echo "3- what process any user is running"
    echo "4- exit"
    read Menu_Option
    case $Menu_Option in
  1)
        echo "THE ANCESTRY TREE FOR CURRENT PROCESS IS...."
        echo " "
        ps -ef > file1
        currentID=$(awk '{if ($3 == '$PPID') print $2}' file1)
        while [ $currentID -gt 0 ]
        do 
            Process_Name=$(awk '{if ($2 == $currentID) print $8 "  " $9}'     file1)

---

我希望以下是您需要的：

#!/bin/sh

Menu_Option=0

echo "WELCOME"
echo "--------------------------------------------------------------"
while [ $Menu_Option -ne 4 ]
do
        echo "select a menu option"
        echo "1- ancestry history"
        echo "2- who is online"
        echo "3- what process any user is running"
        echo "4- exit"
        read -r Menu_Option
        case $Menu_Option in
        1)
                echo "THE ANCESTRY TREE FOR CURRENT PROCESS IS...."
                echo " "
                ps -ef > file1
                currentID=$(awk '{if ($3 == '$PPID') print $2}' file1)
                while [ "$currentID" -gt 0 ]
                do
                        Process_Name=$(awk '{if ($2 == '"$currentID"') print $8 "  " $9}'     file1)
                        echo "$Process_Name"
                        currentID=$(awk '{if ($3 == '"$currentID"') print $2}' file1)
                        if [ "$currentID" = "" ]
                        then
                                currentID=-1;
                        fi
                done
                echo ""
        esac
done

---

您是否检查了

currentID

设置为什么？在设置后添加类似

echo$currentID

的内容，以查看您从

awk

返回了什么。它返回了多个值。我如何解决此问题？如果不知道您的意图以及返回了什么值，很难说清楚。我打算查找当前值进程ID来映射进程树。它返回4个进程ID’不要忘记引用变量，尤其是在

[…]

中。如果不这样做，你只会自找麻烦。（如果你没有弄清楚，这可能会导致错误…）谢谢。我很好奇为什么你在awk声明中使用单引号和双引号。一旦我完成了脚本，我得到了评论和反馈。做出了相应的更改。