Int 21 Fn 64 U - Os/2 V2.1+ Virtual Dos Machine - Get Second Sft Flags W [O]

AH = 64h
DX = 0005h (function number)
CX = 636Ch (magic value, "cl")
BX = 0000h (indicates special request)
DI = DOS file handle

Return: AX = value of second flags word from OS/2 SFT entry for file

Notes: if CX is not 636Ch on entry, INT 21/AH=6Ch is invoked, because a bug
in OS/2 1.x FAPI erroneously called AH=64h instead of AH=6Ch
the OS/2 SFT has two flags words rather than DOS's one word, and this
function provides access to the word which is not present in DOS