RPG - how do we return a parameter using C-style "Return <Value>" syntax

Question

Quick reminder. IN RPG, how do we return a parameter using C-style "Return value" syntax, instead of passing in parameter list? Using RPGLE /free.

// pgm: PARM1                          
dcl-pr PARM2  EXTPGM('PARM2');         
  PrOption  char(1) const;             
  RET       char(5) ;                  
end-pr;                                
                                       
dcl-s RET   char(5) ;                  
                                       
Eval RET='';                           
 callP PARM2('1':RET);                 
*inlr = *on;                           
return;           

// pgm: PARM2                            
dcl-pr PARM2  EXTPGM('PARM2');           
  PrOption  char(1) ;                    
  RET       char(5) ;                    
end-pr;                                  
                                         
dcl-pI PARM2  ;                          
  PrOption  char(1) ;                    
  RET       char(5) ;                    
end-pI;                                  
                                         
// do some stuff                         
Eval Ret= '1';                           
Eval *inlr = *on;                        
//Return RET;                            
return;                   

Answer 1

The RPG programs on IBM i do not support a returned value from a *PGM object.

Returned values are only supported from subprocedures.

// pgm: PARM1                          
dcl-pi PARM1  EXTPGM('PARM1');         
  PrOption  char(1) const;             
  RET       char(5) ;                  
end-pi;                                
                                       
ret = SubProc2('1');                 
*inlr = *on;                           
return; 

dcl-proc SubProc2;
 dcl-pi *n char(5);
   PrOption char(1);
 end-pi;

 return '00001';
end-proc;

*PGM Return codes for RPG and COBOL are handled by the system.

The return codes sent by running RPG IV programs are:

• 0 --> When a program is started, or by the CALL operation before a program is called
• 1 --> When a program ends with LR set on
• 2 --> When a program ends with an error (response of C, D, F, or S to an inquiry message)
• 3 --> When a program ends because of a halt indicator (H1-H9)

ILE C programs
The current value of the integer return code is returned by the last ILE C return statement in an ILE C program.