INT 15 - TopView - "ISOBJ" - VERIFY OBJECT HANDLE
AX = 1016h
ES:DI = possible object handle
Return: BX = FFFFh if ES:DI is a valid object handle
0000h if ES:DI is not
Note:   under DESQview versions prior to 2.50, an object handle is always a
pointer to the object; for versions 2.50 and up, only task handles
are always pointers (other handles may consist of an object number
and offset into DESQview's common memory)
SeeAlso: AX=DE2Bh

Format of object:
Offset  Size    Description
00h    WORD    offset in common memory of previous object of same type
02h    WORD    offset in common memory of next object of same type
04h    WORD    signature FEDCh (DV 2.42-)
signature FEDCh or object number (DV 2.50+)
06h    WORD    object type
08h    DWORD   object handle to return to caller
0Ch    DWORD   canonicalized object address (segment = common memory)
...     varies by object type and DESQview version

See also: 15DE14

151016 - TopView - "ISOBJ" - VERIFY OBJECT HANDLE