Bash脚本编写一般问题(条件和变量传递)

if [ $PASSWORD != 'pass' ]; then

或者更好:

if [ "$PASSWORD" != 'pass' ]; then

如果$PASSWORD为空,将避免失败。

read PASSWORD
if [ "x$PASSWORD" != "xpass" ] ; then
   echo "Wrong. Exiting."
   exit 1
fi
exit 0

您可能想知道两种解决方案 read 命令:

-p string

和

-s

因此,提示输入密码时,您可以执行以下操作:

read -sp "Please enter your password: " PASSWORD
echo

This 是一个很好的资源。

用例/esac构造

read -p "enter: " PASSWORD
case "$PASSWORD" in
    "pass") echo "ok;;
    * ) echo "not ok";;
esac

x=10
y=5
z=1
options=3
expression="$((x> y)) $((y> z)) $((options<=4))"
case "$expression" in
   "1 1 1")
    echo "x > y and y>z and options <=4";;
    *) echo "Not valid";;
esac