CALL
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Transfers program control to a remote program.
CALL
Pgm (Character Expression | Form variable)
ParmList (<u>*NONE</u>| Parameter List Name)
Db (Database Object)
Err (Indicator Variable | *EXTENDED)
Lr (Indicator Variable)
Parameters
Pgm
Required . Pgm specifies the name of the remote program to call.
ParmList
Optional. ParmList specifies the parameter list name. *NONE is the default and indicates that there are no parameters to pass.
Db
Required . Db specifies the database name where the program being Called is located. Database names are defined with the DCLDB command.
Err
Optional. Err determines what the runtime will do if an error occurs while executing this command. The following rules apply:
- Err (Indicator Variable) - the specified Indicator is set if an error occurred.
- Err (*EXTENDED) - a program status flag is set whose status can be checked using the %ERROR built-in function.
- If the Err keyword is not given and an error occurs, a runtime exception will be thrown.
Lr
Optional. The Lr parameter will be set when the last record is read.
Remarks
Use CALL to call an AS/400 program. To call a local program, use CALLB.
Note Currently, a CALL with no DB parameter is converted (by the Compiler) to a CALLB. Programmers are encouraged to use CALLB for local calls in the future.
Calling an AS/400 Program:
When calling an AS/400 program, PGM should include the library name or LIBL, i.e. CALL PGM(“Library/Program”) or CALL PGM(LIBL/Program’). The Call will use the library list associated with the user ID associated with the database name. The library list can be changed by calling the appropriate OS/400 command.
The maximum number of parameters that can be passed in an AS/400 call is 36 . The parameters can be of any simple types (packed, char, date, zoned etc…) or data structures or multiple occurrence data structures.
The AS/400 provides for three parameter data types for Commands (e.g., QCMDEXC) and Programs (CL, RPG, etc): Character, Boolean and Numeric. Typically, numeric parameters are always Packed. You must explicitly declare numeric parameters as Type(*packed) in your Encore RPG code. It may not be presumed that the Encore RPG compiler generates packed numerics.
You can also call AS/400 APIs which can require a data structure as a Parm. This is supported and all required data types are permitted. When redefining data structure subfields, only the first definition is processed and converted between ASCII and EBCDIC.
For Example:
dclDS Name(MYparmDS)
dcldsfld FieldA *char 10 // This value is passed and converted
dcldsfld FieldB *packed len(7,2) // Ignored dcldsfld FieldC *zoned len(9,2) // Ignored
Example
dclDB Name ( ProdDB ) DBName ( "DG Net iSeries" )
DclPlist Listout
Dclparm TimeOfDay Type (*char) Len (10)
Dclparm DayOfWeek Type (*packed) Len (1,0)
Dclparm MonthOfYear Type (*packed) Len (2,0)
// Call to a program with a PList. Call Pgm ( "LIBL/MyProgram" ) DB (ProdDB) ParmList (Listout)
// Call to a program with parms. Call Pgm ( "LIBL/MyProgram" ) DB (ProdDB) ParmList (Listout)
Dclparm TimeOfDay Type (*char) Len (10)
Dclparm DayOfWeek Type (*packed) Len (1,0)
Dclparm MonthOfYear Type (*packed) Len (2,0)