Cancels an outstanding DosSetFileLocks request.

#define INCL_DOSFILEMGR
#include <os2.h>

HFILE        hFile;    /*  File handle used in the DosSetFileLocks function that is to be cancelled. */
PFILELOCK    pflLock;  /*  Address of the structure describing the region to be locked by DosSetFileLocks. */
APIRET       ulrc;     /*  Return Code. */

ulrc = DosCancelLockRequest(hFile, pflLock);