ref：http://bash.cyberciti.biz/guide/Getting_User_Input_Via_Keyboard
You can accept input from the keyboard and assign an input value to a user defined shell variable using .
Contents
ref：http://bash.cyberciti.biz/guide/Getting_User_Input_Via_Keyboard
You can accept input from the keyboard and assign an input value to a user defined shell variable using .
Where,
Create a script called greet.sh as follows:
Save and close the file. Run it as follows:
Sample Outputs:
Enter your name : Vivek Gite Hi,Vivek Gite. Let us be friends!
Try the following examples.
A shell script to display the Internet domain name owner information (domain.sh):
You can time out read command using the -t option. It causes read to time out and return failure if a complete line of input is not read within TIMEOUT seconds. For example,if no input provided within 10 second,program will be aborted (domain2.sh):
The -s option causes input coming from a terminal do not be displayed on the screen. This is useful for password handling (readpass.sh):
Consider the following example:
Sample outputs:
Enter directory to delete : foo bar /tmp/data foo bar /tmp/data
The user supplied three values instead of one. The string is now made of three different fields. All three words are assigned to dirname using internal field separator. The determines how shell recognizes fields.
To display default value of ,enter:
You will see a whitespace which is nothing but a space,a tab,and a newline (default). You can print actual values of IFS using the following command (see ):
Sample outputs:
^I$ $
Where,
Create a variable called nameservers and give it total 3 values as follows (note all values are separated by a whitespace):
Display the value of a variable nameservers with or :
OR
Now,you can simply split $nameservers using the as follows (see ):
Where,
Sample outputs:
DNS Server #1 ns1.nixcraft.net #2 ns2.nixcraft.net #3 ns3.nixcraft.net
Consider the following line:
gitevivek:x:1002:1002::/home/gitevivek:/bin/sh
Assign the above line to a variable called pwd:
Save the Internal Field Separator to a variable called old:
Set the Internal Field Separator to a colon (i.e. change the Internal Field Separator):
Read $pwd and generate tokens using $IFS and store them into respective fields:
Sample outputs:
Your login name is gitevivek,uid 1002,gid 1002,home dir set to /home/gitevivek with /bin/sh as login shell
Finally,restore the Internal Field Separator value using $old:
Where,
