Log for Ubuntu 台灣社群

Command substitution allows the output of a command to replace the
command itself.  Command substitution occurs when a command is enclosed
as follows:
     $(COMMAND)
   or
     `COMMAND`

`ls`

# echo `uname` | rev
xuniL

Bash performs the expansion by executing COMMAND and replacing the command substitution with the standard output of the command, with any trailing newlines deleted.

`ls`