INT 68 - APPC/PC - NETWORK DEVICE CONTROL - ATTACH PHYSICAL UNIT
        AH = 01h subfn 2000h
        DS:DX -> control block
Return: control block updated
SeeAlso: AH=01h/SF=2100h,AH=01h/SF=2B00h

Format of control block:
Offset  Size    Description
 00h 12 BYTEs   reserved
 0Ch    WORD    2000h (verb "Attach Physical Unit")
 0Eh  6 BYTEs   00h
 14h    DWORD   (big-endian) return code (see AH=01h/SF=1B00h)
 18h    WORD    00h
 1Ah    BYTE    version
 1Bh    BYTE    release
 1Ch  8 BYTEs   (big-endian) net name
 24h  8 BYTEs   (big-endian) physical unit name
 2Ch  8 BYTEs   00h
 34h    DWORD   pointer to SYSTEM_LOG_EXIT routine, FFFFFFFFh=don't log errors
                (see also AH=01h/SF=2100h)
 38h    DWORD   00h
 3Ch    BYTE    00h RETURN_CONTROL: COMPLETE
                01h RETURN_CONTROL: INCOMPLETE

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