10.10. Command Substitution

10.10.1. Backquotes

A string or variable can be assigned the output of a Linux command by placing the command in back quotes. This is called command substitution. (On the keyboard, the back quotes are normally below the tilde character.) If the output of a command is assigned to a variable, it is stored as a wordlist or array. (See "Wordlists and Command Substitution" .)

Example 10.77. 
1  > echo The name of my machine is `uname -n`.
						The name of my machine is stardust.

2  > echo The present working directory is `pwd`.
						The present working directory is /home/stardust/john.

3  >set d = `date`
   > echo $d
						Tue Mar 28 14:24:21 PDT 2000

Explanation

  1. The Linux command uname -n is enclosed in back quotes. When the shell encounters ...

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