This example uses DosKillProc to kill itself. It creates and opens a queue as a way of getting the PID for the process. In the end, it sleeps for up to 45 seconds, to ensure that the process was killed by this API.

#define INCL_DOSQUEUES   /* DOS Queue values */
#define INCL_DOSPROCESS  /* DOS thread and process values */
#define INCL_DOSERRORS   /* DOS error values */
#include <os2.h>
#include <stdio.h>
#include <string.h>

int main(USHORT argc, PCHAR argv[]) {

   PSZ         szQueueName  = "\\QUEUES\\OF\\DATA\\WAITING\\FOR\\SERVICE";
   HQUEUE      hqSpecialQue = NULLHANDLE; /* Queue handle                   */
   REQUESTDATA Request      = {0};        /* Reques */
   PID         pidOwner     = 0;
   APIRET      rc           = NO_ERROR;   /* Return code                    */

   rc = DosCreateQueue(&hqSpecialQue,    /* Queue handle                    */
             QUE_FIFO |                  /* First-In First-Out order        */
             QUE_CONVERT_ADDRESS,        /* Convert 16-bit addresses to 32  */
             szQueueName);               /* Name of the queue to create     */

   if (rc!= NO_ERROR) {
      printf ("DosCreateQueue error: return code = %u\n", rc);
      return 1;       }

   rc = DosOpenQueue (&pidOwner,         /* PID of queue owner              */
                      &hqSpecialQue,     /* Handle for created queue        */
                      szQueueName);      /* Name of the queue to open       */

   if (rc!= NO_ERROR) {
      printf ("DosOpenQueue error: return code = %u\n", rc);
      return 1;       }

           /* Kill the queue owner (which is us) */

   rc = DosKillProcess(0, pidOwner);
   if (rc != NO_ERROR) {
      printf("DosKillProcess error: return code = %u\n", rc);
      return 1;
   }

   rc = DosSleep(45000L);    /* Dead code */

   return NO_ERROR;
}