Two representations of logic and in shell

There are two ways to represent logic in bash:

(1) [$state = = "Running"-a $name = = "Zone1"]

(2) [[$state = = "Running" && $name = = "Zone1"]]

The second type is supported in Ksh.

Instance:

#! /bin/-P "pelease input your name:"-P "pleaase Input your password:" passwdif [$name = = "Root"-a $passwd = = "123" ]; Then    "Login successful! "Else    " Login failed! "fiif [[$name = =" Root "&& $passwd = =" 123 " ]]; Then       "Login Pass"else    "login fail"fi    

Output Result:
Pelease Input your Name:root
Pleaase Input your password:123
Login Successful!
Login Pass

The use of read-p in Ksh seems to be problematic and will appear./learn_shell.save[2]: Read:no query process, such an error message.

So change to the following form:

(1) The first kind

echo "ThePrompt\c"

read TheSomthing

echo $TheSomething

(2) The second type

read TheSomething?‘ThePrompt‘

The subtle difference is that the first type of prompt is followed by a carriage return, and the second does not enter.

Instance:

#! /usr/bin/"Pelease Input your Name:"read Nameread passwd? " Pleaase Input your password: "if [[$name = =" Root "&& $passwd = =" 123 " ]]; Then       "Login Pass"else    "login fail"fi    #. /learn_shell.save pelease Input your name:    (This place has a carriage return)123Login Pass

Two representations of logic and in shell