How would I create my own CBL_ALLOC_MEM and CBL_FREE_MEM routines?

Here are some examples:

       IDENTIFICATION DIVISION.
       PROGRAM-ID. CBL_ALLOC_MEM.
       ENVIRONMENT DIVISION.
       DATA DIVISION.
       LINKAGE SECTION.
       01 LNK-MEM-POINTER      POINTER.
       01 LNK-MEM-SIZE         UNSIGNED-INT.
       01 LNK-FLAGS            UNSIGNED-INT.
       PROCEDURE DIVISION USING LNK-MEM-POINTER
                                LNK-MEM-SIZE 
                                LNK-FLAGS. 
       MAIN.
            IF LNK-MEM-SIZE GREATER THAN ZERO 
                CALL "calloc" USING BY VALUE 1
                              BY VALUE LNK-MEM-SIZE
                              RETURNING LNK-MEM-POINTER
            END-IF.
            GOBACK.

		
		
		
		
		
       IDENTIFICATION DIVISION.
       PROGRAM-ID. CBL_FREE_MEM.
       ENVIRONMENT DIVISION.
       DATA DIVISION.
       LINKAGE SECTION.
       01 LNK-MEM-POINTER      POINTER.
       PROCEDURE DIVISION USING LNK-MEM-POINTER.
       MAIN.
            IF LNK-MEM-POINTER NOT EQUAL TO ZERO 
                CALL "free" USING BY VALUE LNK-MEM-POINTER
            END-IF.
            GOBACK.
		
		
		
		
		
Note that both of the above programs must be compiled with the -cp POINTER compatibility option. 
		
		
		
		
		
On Windows the calloc() and free() functions are in MSVCRT.DLL which must be preloaded by specifying iscobol.shared_library_list=msvcrt.dll. 
		
		
		
		
		
For example, the following test program allocates and frees 100 bytes:
		
		
		
		
		

				
		
		
		
		
id division.
program-id. test.
data division.
working-storage section.
77 mem-ptr usage pointer.
procedure division.
main-logic.
   call "CBL_ALLOC_MEM" using mem-ptr, by value 100, by value 0.
   call "CBL_FREE_MEM" using by value mem-ptr.
		
		
To compile and run:
		
		
iscc -cp CBL_ALLOC_MEM.cbl
iscc -cp CBL_FREE_MEM.cbl
iscc -cp test.cbl
java -Discobol.shared_library_list=msvcrt.dll TEST
		
		


				

Article ID: 15
Created: August 28, 2009
Last Updated: August 28, 2009
Author: Support KB Author

Online URL: https://support.veryant.com/phpkb/article.php?id=15