any pointers on implementing linked list in cobol????

ashimer · Posted: Tue Sep 26, 2006 11:52 am

hi

can anyone give me some sample codes to understand how to implement linked list or b-tree or b-list in cobol using pointers .....

thanks

UmeySan · Posted: Tue Sep 26, 2006 4:53 pm

Hi !

First i hope i understand you correctly. I think you wanna know something abaout using pointers in Cobol. Pointers are nothing else then adresses of areas. So the area could be filled with data fom another called programm without transfering the whole area from the calling-programm to the called-programm. You only transfer the adress of the area or the table by a pointer variable.

LINKAGE SECTION.

01 LINK-PARM-MDL00900.

05 LINK-MDL00900-PGMMODE PIC X(02).
05 LINK-MDL00900-PGMFUNK PIC X(02).
05 LINK-MDL00900-ADRESSE POINTER.
05 LINK-MDL00900-KONTONR PIC X(06).
05 LINK-MDL00900-KONTOKZ PIC X(03).
05 LINK-MDL00900-RETCODE PIC X(04).
05 LINK-MDL00900-RETMSGS PIC X(30).

PROCEDURE DIVISION USING LINK-PARM-MDL00900.

IF LINK-MDL00900-PGMMODE = '01'

SET ADDRESS OF ACCOUNT-TAB TO LINK-MDL00900-ADRESSE

....then fill the account-tab with needed data
.....and return to the calling programm

END-IF

If tis is what you want, please read more in the cobol-manual about using pointers.

Regards, UmeySan

DavidatK · Posted: Tue Sep 26, 2006 10:39 pm

ashimer,

To start with, what is your understanding of linked-lists? Do you understand the structure? And are you interested in implementing a forward linked list or a bi-directional (forward and backward) linked list?

Dave