Arbortext Command Language > Using the Arbortext Command Language > Back-quotes
  
Back-quotes
Information can be processed by either Arbortext Editor, using ACL, or it can be passed to the operating system shell for processing. Various features of Arbortext Editor allow you to pass information between the shell and Arbortext Editor.
The back-quotes (opening single quotes) perform a function similar to the sh command. Any command placed in back-quotes (` `) is also executed in a Bourne subshell. The difference is that the command returns what would normally be piped to standard output (as the sh command does). Therefore the result of the command has to be assigned to a variable. For example to evaluate the user name the following command can be applied:
$username =`whoami`message "$username"
As a second example, the following command extracts the current date from the system and assigns it to a variable:
$today=`date '+%y-%m-%d' `
This sequence runs the command date '+%y-%m-%d' in the UNIX shell and assigns the result to the variable $today. The value for this variable might be something like "93-08-25".
Like the shell, runs of white space in the output (such as blanks, tabs, newlines, and so on) are replaced with a single blank character.