read: Reading Input from User

The following short example shows how read can be used to get input from the user:

    #!/bin/sh
    echo "Please enter your name: \c"
    read NAME
    echo "Your name is $NAME."
    exit 0

The c means that the line feed will be suppressed, so that the prompt sits at the end of the line, not at the beginning of the following line.

Two more common controls available to the echo command are to use n to add a line feed, and t to add a tab.

Multiple values may be read on a single line by using:

    #!/bin/sh
    echo "Please enter two numbers: \c"
    read NUM1 NUM2
    echo The numbers entered are $NUM1 and $NUM2
    exit 0

This ensures that if two numbers are entered on a single line, they will be read within two variables. If three numbers were entered, the second variable (NUM2) would contain the last two numbers.

Assuming three numbers were the input of the above example, the first two numbers could be assigned to the first variable by entering them as

num1 num2 num3

The backslash ( ) allows the blank space between num1 and num2 to be part of the variable (ordinarily, spaces are used as field seperators.