This example removes a child session from a window list.

#define INCL_DOSPROCESS   /* DOS process values - needed for DosSleep */
#define INCL_DOSSESMGR
#define INCL_DOSERRORS
#include <stdio.h>
#include <os2.h>

int main(VOID) {
   STARTDATA SData       = {0};
   PSZ       PgmTitle    = "Not in the Window List",    /* Title      */
             PgmName     = "CMD.EXE";  /* This starts an OS/2 session */
   APIRET    rc          = NO_ERROR;   /* Return code                 */
   PID       pid         = 0;          /* PID returned                */
   ULONG     ulSessID    = 0;          /* Session ID returned         */
   UCHAR     achObjBuf[100] = {0};     /* Error info if start fails   */
   STATUSDATA ChildStatus   = {0};     /* Child status data           */

   SData.Length  = sizeof(STARTDATA);
   SData.Related = SSF_RELATED_CHILD;       /* A dependent session          */
   SData.FgBg    = SSF_FGBG_FORE;           /* start session in foreground  */
   SData.TraceOpt = SSF_TRACEOPT_NONE;      /* No trace                     */
             /* Start an OS/2 session using "CMD.EXE /K" */
   SData.PgmTitle = PgmTitle;
   SData.PgmName = PgmName;
   SData.PgmInputs = "/K";                     /* Keep session up           */
   SData.TermQ = 0;                            /* No termination queue      */
   SData.Environment = 0;                      /* No environment string     */
   SData.InheritOpt = SSF_INHERTOPT_SHELL;     /* Inherit shell's environ.  */
   SData.SessionType = SSF_TYPE_WINDOWABLEVIO; /* Windowed VIO session      */
   SData.IconFile = 0;                         /* No icon association       */
   SData.PgmHandle = 0;
   SData.PgmControl = SSF_CONTROL_VISIBLE | SSF_CONTROL_MAXIMIZE;
   SData.InitXPos  = 30;     /* Initial window coordinates              */
   SData.InitYPos  = 40;
   SData.InitXSize = 200;    /* Initial window size */
   SData.InitYSize = 140;
   SData.Reserved = 0;
   SData.ObjectBuffer  = achObjBuf; /* Contains info if DosExecPgm fails */
   SData.ObjectBuffLen = (ULONG) sizeof(achObjBuf);
   rc = DosStartSession(&SData, &ulSessID, &pid);  /* Start the session */
   if (rc != NO_ERROR) {
      printf ("DosStartSession error : return code = %u\n", rc);
      return 1;
   }
   printf("Removing child process from the Window List... \n");

   ChildStatus.Length = sizeof(STATUSDATA);
   ChildStatus.SelectInd = SET_SESSION_NON_SELECTABLE;
   ChildStatus.BondInd = SET_SESSION_UNCHANGED;

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

   printf("\nPress Ctrl-Esc  The child is no longer listed.\n");
   printf("\nProgram will terminate in 10 seconds...\n");
   rc = DosSleep(10000L);  /* wait 10 seconds */

   return NO_ERROR;
}