16-bit signed binary integer with extern "COBOL"

Sample C++ usage COBOL subroutine
#include <stdio.h>
#include <stdlib.h>
extern "COBOL" {void COBRTN
(short int*);}

int main()
{
  short int x;
  x=5;
  COBRTN(&x);   /* x by reference */
  exit(0);
}
IDENTIFICATION DIVISION.
PROGRAM-ID. COBRTN.
ENVIRONMENT DIVISION.
DATA DIVISION.
LINKAGE SECTION.
01 X PIC S9(4) BINARY.
PROCEDURE DIVISION USING X.
     DISPLAY X
     GOBACK.
END PROGRAM COBRTN.