Gets a new handle for an open file.

#define INCL_DOSFILEMGR
#include <os2.h>

HFILE     hFile;   /*  File handle to duplicate, or alias. */
PHFILE    pHfile;  /*  A pointer to the HFILE in which file handle informtion is stored. */
APIRET    ulrc;    /*  Return Code. */

ulrc = DosDupHandle(hFile, pHfile);