Learning Linux Shell Scripting

The here string and the <<< operator

The here string is used for input redirection from text or a variable. Input is mentioned on the same line within single quotes ('').

The syntax is as follows:

$ command <<< 'string'

1. Let's see the following example hereString_01.sh:

   #!/bin/bash
   wc –w <<< 'Good Morning and have a nice day !'

2. Save the file, give the permission, and run the script as follows:

   $ chmod u+x hereString_01.sh
   $ ./hereString_01.sh
   

3. Here is the output:

   8
   

In this example, the string Good Morning and have a nice day ! is called as the here string.