Implementing an OS Service

Uniface enables you use an operating system service to send commands and return output from an operating system.

To create and use an OS service:

Create a signature for an operating system service with the Implementation Type set to Operating System Command.
Two default, non-editable operations are available, COMMAND and COMMANDOUT.
In the calling component, call the OS service using the activate statement.
For example, if you created a component called OSUNIX:
```
activate "OSUNIX".COMMAND("at -fm myscript now")
activate "OSUNIX".COMMANDOUT("ls -l mydir", $LISTING$)
```
Output is passed to the $LISTING$ variable.
In your application’s assignment file, specify a path that directs the operating system component to the operating system server.
For example:
```
[PATHS]
$SERVER1:=TCP:PHOENIX|leda|?|CSV

[SERVICES_EXEC]
OSUNIX=$SERVER1:OSUNIX
```