Command Substitution

Bash Prompt HOWTO:
Prev | Chapter 3. Bash Programming and Shell Scripts | Next

# 3.3. Command Substitution

In almost all cases in this document, I use the $(<command>) convention for command substitution: that is,

    $(date +%H%M)

means "substitute the output from the `date +%H%M` command here." This works in Bash 2.0+. In some older versions of Bash, prior to 1.14.7, you may need to use backquotes (``date +%H%M``). Backquotes can be used in Bash 2.0+, but are being phased out in favor of $(), which nests better. If you're using an earlier version of Bash, you can usually substitute backquotes where you see $(). If the command substitution is escaped (ie. \$(command) ), then use backslashes to escape BOTH your backquotes (ie. \'command\' ).

Prev | Home | Next
Quotes and Special Characters | Up | Non-Printing Characters in Prompts