Int 2F Fn 5401  U - Power.exe - Get/set Power Status                       [p]

   AX = 5401h
   BH = function
       00h get status

       Return: BL = current power management status (see #2523)
       01h set status
       BL = new power managment status (see #2523)

Return: AX = function status (see #2524)

Note:  called by MS Windows 3.1 POWER.DRV

See Also: AH=53h,AX=5400h,AX=5402h,AX=5403h

Bitfields for power management status:
Bit(s) Description (Table 2523)
 0 POWER.EXE power management enabled
 1 APM firmware power management enabled
 2-7   reserved (0)

Notes: bit 1 is ignored if there is no APM firmware
   bits 1-0: 00 = POWER OFF, 10 = POWER STD, 11 = POWER ADV

(Table 2524)
Values for POWER.EXE function status:
 0000h successful
 0002h "ERROR_PM_ALREADY_CONNECTED"
 0003h "ERROR_PM_NOT_CONNECTED"
 0087h "ERROR_PM_INVALID_PARAMETER"