IoGetContainerInformation function (wdm.h)

The IoGetContainerInformation routine provides information about the current state of a user session.

Syntax

NTSTATUS IoGetContainerInformation(
  [in]           IO_CONTAINER_INFORMATION_CLASS InformationClass,
  [in, optional] PVOID                          ContainerObject,
  [in, out]      PVOID                          Buffer,
  [in]           ULONG                          BufferLength
);

Parameters

[in] InformationClass

Specifies the class of events for which the caller (driver) requests information. Set this parameter to the following IO_CONTAINER_INFORMATION_CLASS enumeration value:

• IoSessionStateInformation

For more information, see the following Remarks section.

[in, optional] ContainerObject

A pointer to an opaque, system object supplied by the I/O manager. For InformationClass = IoSessionStateInformation, set this parameter to the SessionObject parameter value that is provided by the I/O manager during the call to the driver's IO_SESSION_NOTIFICATION_FUNCTION function.

[in, out] Buffer

A pointer to a caller-allocated buffer into which this routine writes the state information for the event class specified by InformationClass. For InformationClass = IoSessionStateInformation, the routine writes an IO_SESSION_STATE_INFORMATION structure to the buffer. The buffer must be large enough to contain this structure.

[in] BufferLength

The size, in bytes, of the buffer pointed to by Buffer. For InformationClass = IoSessionStateInformation, BufferLength must be at least sizeof(IO_SESSION_STATE_INFORMATION).

Return value

IoGetContainerInformation returns STATUS_SUCCESS if the call is successful. Possible error return values include the following:

Return code	Description
STATUS_INVALID_PARAMETER_1	Parameter InformationClass is not a valid IO_CONTAINER_INFORMATION_CLASS enumeration constant.
STATUS_INVALID_PARAMETER_2	Parameter ContainerObject is NULL.
STATUS_INVALID_PARAMETER_4	Parameter BufferLength is too small for the information class specified by InformationClass.

Remarks

This routine can potentially support queries for a variety of information classes. In Windows 7, this routine supports only queries for IoSessionStateInformation information, which is status information about user sessions.

Requirements

Requirement	Value
Minimum supported client	Available in Windows 7 and later versions of the Windows operating system.
Target Platform	Universal
Header	wdm.h (include Wdm.h, Ntddk.h, Ntifs.h, Fltkernel.h)
Library	NtosKrnl.lib
DLL	NtosKrnl.exe
IRQL	<= APC_LEVEL

See also

IO_CONTAINER_INFORMATION_CLASS

IO_CONTAINER_NOTIFICATION_CLASS

IO_SESSION_STATE_INFORMATION