How to pass data from one internal session to another

Question

Hi SAP Experts,
How to pass data from one internal session to another and from One external session to another external session. I used import and export parmeter and SPA/GPA parameters. What is the other way to pass data?
Please tel me urgently
Thank you
Basu

Answer 1

Memory Structures of an ABAP Program
In the Overview of the R/3 Basis System you have seen that each user can open up to six R/3 windows in a single SAPgui session. Each of these windows corresponds to a session on the application server with its own area of shared memory.
The first application program that you start in a session opens an internal session within the main session. The internal session has a memory area that contains the ABAP program and its associated data. When the program calls external routines (methods, subroutines or function modules) their main program and working data are also loaded into the memory area of the internal session.
Only one internal session is ever active. If the active application program calls a further application program, the system opens another internal session. Here, there are two possible cases: If the second program does not return control to the calling program when it has finished running, the called program replaces the calling program in the internal session. The contents of the memory of the calling program are deleted. If the second program does return control to the calling program when it has finished running, the session of the called program is not deleted. Instead, it becomes inactive, and its memory contents are placed on a stack.
The memory area of each session contains an area called ABAP memory. ABAP memory is available to all internal sessions. ABAP programs can use the EXPORT and IMPORT statements to access it. Data within this area remains intact during a whole sequence of program calls. To pass data to a program which you are calling, the data needs to be placed in ABAP memory before the call is made. The internal session of the called program then replaces that of the calling program. The program called can then read from the ABAP memory. If control is then returned to the program which made the initial call, the same process operates in reverse.
All ABAP programs can also access the SAP memory. This is a memory area to which all sessions within a SAPgui have access. You can use SAP memory either to pass data from one program to another within a session, or to pass data from one session to another. Application programs that use SAP memory must do so using SPA/GPA parameters (also known as SET/GET parameters). These parameters are often used to preassign values to input fields. You can set them individually for users, or globally according to the flow of an application program. SAP memory is the only connection between the different sessions within a SAPgui.
The following diagram shows how an application program accesses the different areas within shared memory:
In the diagram, an ABAP program is active in the second internal session of the first main session. It can access the memory of its own internal session, ABAP memory and SAP memory. The program in the first internal session has called the program which is currently active, and its own data is currently inactive on the stack. If the program currently active calls another program but will itself carry on once that program has finished running, the new program will be activated in a third internal session.
Data Clusters in ABAP Memory
You can store data clusters in ABAP memory. ABAP memory is a memory area within the internal session (roll area) of an ABAP program and any other program called from it using CALL TRANSACTION or SUBMIT.
ABAP memory is independent of the ABAP program or program module from which it was generated. In other words, an object saved in ABAP memory can be read from any other ABAP program in the same call chain. ABAP memory is not the same as the cross-transaction global SAP memory. For further information, refer to Passing Data Between Programs.
This allows you to pass data from one module to another over several levels of the program hierarchy. For example, you can pass data
From an executable program (report) to another executable program called using SUBMIT.
From a transaction to an executable program (report).
Between dialog modules.
From a program to a function module.
and so on.
The contents of the memory are released when you leave the transaction.
To save data objects in ABAP memory, use the statement EXPORT TO MEMORY.
Saving Data Objects in Memory
To read data objects from memory, use the statement IMPORT FROM MEMORY.
Reading Data Objects from Memory
To delete data clusters from memory, use the statement FREE MEMORY.
Deleting Data Clusters from Memory
please read this which provide more idea about memory
Message was edited by:
        sunil kumar