How to write a sqlite callback in cobol?

@weldon_huels 

SQLite callbacks are typically written in C or other programming languages that are compatible with C. Cobol is not one of those languages. However, if you need to use SQLite with Cobol, you may be able to use an interface library like the OpenCOBOL or GNU Cobol compiler to call C functions.

Assuming you have access to a C compiler and a Cobol compiler that supports C interoperability, you can create a callback function in C and call it from Cobol using the C interface.

Here's an example of how you might write a SQLite callback in C:

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#include <sqlite3.h>

int my_callback(void *data, int argc, char **argv, char **col_names) {
    /* Do something with the callback data */
    return 0;
}

To call this function from Cobol, you would need to define the function prototype in your Cobol program and use the CALL statement to call it:

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IDENTIFICATION DIVISION.
PROGRAM-ID. MYPROGRAM.

DATA DIVISION.
LINKAGE SECTION.
01  DATA-STRUCT.
    05  FILLER                 PIC X(4)   VALUE NULL.
    05  ARG-COUNT              PIC S9(4)  VALUE 0.
    05  ARGV                   POINTER   VALUE NULL.
    05  COL-NAMES              POINTER   VALUE NULL.
PROCEDURE DIVISION.
MAIN.
    CALL "my_callback" USING DATA-STRUCT.
    ...

Note that in order for this to work, you would need to compile the C code into a shared library (such as a DLL or SO file) that can be loaded at runtime by the Cobol program. You would also need to make sure that the SQLite library is linked to both the C and Cobol programs.

@weldon_huels 

It's important to note that the approach described above involves using C as an intermediary layer to call the SQLite callback function from your Cobol program. Cobol itself does not have a direct way to define and invoke SQLite callbacks.

If you prefer to work exclusively in Cobol without relying on a C intermediary layer, you may consider using a Cobol-friendly database system that supports callbacks or equivalent functionality.