Bash 错误：“[y 命令未找到”

Question

我试图让这个脚本正常运行，但我得到./passmark.sh line 7: [y command not found.

这是我的脚本

#!/bin/bash
# A simple script to ask a user for a pass mark and then display a grade
# the grade will be either an A, B, C, D or F
#
CONT=y
echo
while [$CONT = "y" ]
do
        echo -e "\"Please enter a pass mark: \c \""
        read MARK
        if [$MARK -ge "0" -a $MARK -lt "50"] ; then
                echo -e "\n \"F\" \n"
        elif [$MARK -ge "50" -a $MARK -lt "60"] ; then
                echo -e "\n \"D\" \n"
        elif [$MARK -ge "60" -a $MARK -lt "70"] ; then
                echo -e "\n \"C\" \n"
        elif [$MARK -ge "70" -a $MARK -lt "80"] ; then
                echo -e "\n \"B\" \n"
        elif [$MARK -ge "80" -a $MARK -lt "100"] ; then
                echo -e "\n \"A\" \n"
        else
                echo -e "\"Invalid input!!\n \""
        fi
        echo -e "\"Would you like to enter another pass mark? (y/n) \c \""
        read REPLY
        case "$REPLY" in
                n | N | no | No | NO ) CONT=n ;;
                *) ;;
        esac
echo
done 

Answer 1

您在[and周围需要空格]，例如

if [ "$MARK" -ge 0 -a "$MARK" -lt 50 ]; then

你写这样的，当时$MARK是7，它试图执行[7的，而不是通过命令7作为参数传递给该[命令（[仅仅是一个简短的名称test）。

您还应该引用变量。否则，如果用户输入一个空行或多个单词，将无法正确解析测试表达式。