[python-win32] How to find the current/last system state from Python

[Tim Golden]

On 04/07/2012 06:01, prashant padaganur wrote:
> On 03/07/2012 12:23, prashant padaganur wrote:
>>>/ 
> />>/ I want to write an application that puts the system in to different
> />>/ sleep states. Like S0,S1...S4.
> />>/ 
> />>/ Before changing from one state to another I want to know the
> />>/ current/previous sleep state. 
> />>/ 
> />>/ For Ex: If the current state is S0 then I want to put it to S1. Or if
> />>/ the previous state was S3 then I want to put the system to S4.
> />>/ 
> />>/ I want to know how can I get this state info from python using Win32
> />>/ apis. The related struct I found on MSDN is SYSTEM_POWER_STATE 
> />>/ 
> />>/ http://msdn.microsoft.com/en-us/library/windows/desktop/aa373227(v=vs.85).aspx
> />
>>Chances are that WMI can do it: try Googling for "WMI power management"
>>or something similar
>>
>>TJG
> 
> No luck so far. If anyone has done something similar please share your thoughts.


Well I haven't, but I Googled for "WMi power management", found this as
the 3rd hit:

  http://www.vbsedit.com/scripts/desktop/info/scr_233.asp


which led me to look at this page in MSDN:


http://msdn.microsoft.com/en-us/library/windows/desktop/aa394102%28v=vs.85%29.aspx


and the PowerState attribute:


"""
PowerState

    Data type: uint16
    Access type: Read-only

    Current power state of a computer and its associated operating
system. The power saving states have the following values: Value 4
(Unknown) indicates that the system is known to be in a power save mode,
but its exact status in this mode is unknown; 2 (Low Power Mode)
indicates that the system is in a power save state, but still
functioning and may exhibit degraded performance; 3 (Standby) indicates
that the system is not functioning, but could be brought to full power
quickly; and 7 (Warning) indicates that the computer system is in a
warning state and a power save mode. This property is inherited from
CIM_UnitaryComputerSystem.

    Value	Meaning

    0 (0x0)
    Unknown

    1 (0x1)
    Full Power

    2 (0x2)
    Power Save - Low Power Mode

    3 (0x3)
    Power Save - Standby

    4 (0x4)
    Power Save - Unknown

    5 (0x5)
    Power Cycle

    6 (0x6)
    Power Off

    7 (0x7)
    Power Save - Warning
"""

which looks to me very similar to the SYSTEM_POWER_STATE struct you
referenced from MSDN. Can you say whether this is what you're looking for?

<code>
import wmi

c = wmi.WMI()
for sys in c.Win32_ComputerSystem():
  print sys.PowerState

</code>


TJG