This example uses DosStartSession to execute a CHKDSK on the current drive in an OS/2 window, and uses DosSleep to wait 30 seconds before terminating.

#define INCL_DOSPROCESS
#define INCL_DOSSESMGR
#define INCL_DOSERRORS
#include <stdio.h>
#include <os2.h>

int main(VOID) {
   STARTDATA SData   = {0};
   PSZ       PgmTitle    = "CHKDSK for Current Drive",  /* Title      */
             PgmName     = "CHKDSK.COM";  /* Want to run CHKDSK       */
   APIRET    rc          = NO_ERROR;   /* Return code                 */
   PID       pidChild    = 0;          /* PID returned                */
   ULONG     ulSessID    = 0;          /* Session ID returned         */
   UCHAR     achObjBuf[100] = {0};     /* Buffer for error info       */

   SData.Length  = sizeof(STARTDATA);
   SData.Related = SSF_RELATED_CHILD;       /* Start a child session        */
   SData.FgBg    = SSF_FGBG_FORE;           /* Start session in foreground  */
   SData.TraceOpt = SSF_TRACEOPT_NONE;      /* No trace                     */

   SData.PgmTitle = PgmTitle;
   SData.PgmName = PgmName;
   SData.PgmInputs = ""; /* No parameters                                   */

   SData.InheritOpt = SSF_INHERTOPT_SHELL;     /* Inherit shell's environ.  */
   SData.SessionType = SSF_TYPE_WINDOWABLEVIO; /* Windowed VIO session      */
   SData.PgmControl = SSF_CONTROL_VISIBLE | SSF_CONTROL_NOAUTOCLOSE;
   SData.InitXPos  = 30;     /* Initial window coordinates                  */
   SData.InitYPos  = 40;
   SData.InitXSize = 200;    /* Initial window size                         */
   SData.InitYSize = 140;
   SData.ObjectBuffer  = achObjBuf; /* Contains info if DosExecPgm fails    */
   SData.ObjectBuffLen = (ULONG) sizeof(achObjBuf);

   rc = DosStartSession(&SData, &ulSessID, &pidChild);  /* Start CHKDSK     */
   if (rc != NO_ERROR) {
      printf ("DosStartSession error : return code = %u\n", rc);
      return 1;
   } else {
      printf ("Child process has SessID of %u and PID of %u.\n", ulSessID,pidChild);
   }

   printf ("Waiting 30 seconds before terminating...\n");

   rc = DosSleep(30000L);         /* Wait 30 seconds for child to complete */
   if (rc != NO_ERROR) {
      printf ("DosSleep error : return code = %u\n", rc);
      return 1;
   }

   return NO_ERROR;
  }