13.10. Command Substitution

13.10.1. Backquotes

A string or variable can be assigned the output of a UNIX command by placing the command in backquotes. This is called command substitution. (On the keyboard, the backquotes 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” on page 919.)

Example 13.77. 
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 2001

EXPLANATION

  1. The UNIX command uname -n is enclosed in backquotes. When the shell ...

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