Dialog modules are defined using the following pair of statements:
The OUTPUT addition defines the dialog module mod as one that may be called from the PBO event of the flow logic of any screen.
The INPUT addition defines the dialog module mod as one that may be called from the PAI event of the flow logic of any screen. INPUTis the standard addition. It may be omitted.
You can define two dialog modules, both called mod, in the same program as long as one of them has the addition OUTPUT and the other has the addition INPUT.
Dialog modules do not have local data areas. All declarative statements in dialog modules are handled with the global data declarations in the program. You should therefore include all of your declarations at the start of the program (see also Structure of ABAP Programs).