Create a DHERRNO variable.  Possible values:

	1. Out of memory.
	2. Disk write failed.
	3. Disk read failed.
	4. Seek failed.
	5. Consistency error in folder.

/* DHERRNO values */

#define DHERR_NOERR		0	/* no error			     */
#define DHERR_NOMEM		1	/* couldn't allocate memory          */
#define DHERR_BADWRITE		2	/* write failed (including no space) */
#define DHERR_BADREAD		3	/* read failed			     */
#define DHERR_BADSEEK		4	/* seek failed (see FLDCORRUPT)      */
#define DHERR_FLDCORRUPT	5	/* folder structure corrupt	     */
#define DHERR_BADDOCID		6	/* invalid docid/handle 	     */
#define DHERR_BADFLDID		7	/* invalid folder id/handle	     */