The Command extension enables the execution of Multi-Line Commands from Terminal prompt.
Terminal Multi-Line Input with Edit, Insert, Delete, Print extension for IRIS and Caché
IRIS and Caché have just single command lines in terminal available
This Multi-Line Commands Editor also will execute the Multi-line Commands.
In addition, it is independent of access to %SYS and can be installed in any namespace
Special thanks to @Jeffrey Drumm who inspired me to this and supported me as beta-tester.