This example attempts to obtain the handle of a dynamic link module named "DISPLAY.DLL," and then tests whether it is currently loaded or not.

#define INCL_DOSMODULEMGR   /* Module Manager values */
#define INCL_DOSERRORS      /* DOS Error values */
#include <os2.h>
#include <stdio.h>

int main(VOID) {
   PSZ     ModuleName    = "C:\\OS2\\DLL\\DISPLAY.DLL";  /* Module name   */
   HMODULE ModuleHandle  = NULLHANDLE;                   /* Module handle */
   APIRET  rc            = NO_ERROR;                     /* Return code   */

   rc = DosQueryModuleHandle(ModuleName,      /* Module to look for       */
                             &ModuleHandle);  /* Handle (returned)        */
   if (rc != NO_ERROR) {
      printf("DosQueryModuleHandle error: return code = %u\n", rc);
      return 1;
   } else {
      printf ("Module handle = %u\n", ModuleHandle);
   }

   rc = DosQueryModuleName (ModuleHandle,   /* Module handle to query     */
                            256L,           /* Maximum length of result   */
                            ModuleName);    /* Module name returned       */

   if (rc != NO_ERROR) {
      printf("DosQueryModuleName error: return code = %u\n", rc);
      return 1;
   } else {
      printf ("Module name = %s\n", ModuleName);
   }
   return NO_ERROR;
}