RC.
ARexx commands return the following codes:
0 Command executed succesfully.
1 Command executed succesfully, but there is some condition that might be of interest.
5 The command was syntactically valid, but could not be completed for some reason.
10 You supplied invalid arguments for this command.
11 You submitted an unknown command.
20 There was an internal error. The command is not executed.
Commands
ARexx