ACPI_EVAL_INPUT_BUFFER_V1 structure (acpiioct.h)

The ACPI_EVAL_INPUT_BUFFER structure is used as input to an IOCTL_ACPI_EVAL_METHOD request and to an IOCTL_ACPI_ASYNC_EVAL_METHOD request. The structure supplies the name of a control method that does not take an input argument.

Syntax

typedef struct _ACPI_EVAL_INPUT_BUFFER_V1 {
  ULONG Signature;
  union {
    UCHAR MethodName[4];
    ULONG MethodNameAsUlong;
  } DUMMYUNIONNAME;
} ACPI_EVAL_INPUT_BUFFER_V1, *PACPI_EVAL_INPUT_BUFFER_V1, ACPI_EVAL_INPUT_BUFFER, *PACPI_EVAL_INPUT_BUFFER;

Members

Signature

The signature of an input buffer that does not include an argument, which must be set to ACPI_EVAL_INPUT_BUFFER_SIGNATURE.

DUMMYUNIONNAME

DUMMYUNIONNAME.MethodName[4]

A four-element ASCII character array that contains the name of a control method, for example, 'ABCD.'

DUMMYUNIONNAME.MethodNameAsUlong

A value of type ULONG that contains the name of the method in the format (ULONG) ('DCBA'), where the method name is the four-element ASCII character array 'ABCD.'

Remarks

If a device supports a control method named 'ABCD' that does not take an input argument, a driver for the device can evaluate the method by sending an IOCTL_ACPI_EVAL_METHOD request or an IOCTL_ACPI_ASYNC_EVAL_METHOD request to the device and setting the members of the input ACPI_EVAL_INPUT_BUFFER structure as follows:

  • Set Signature to ACPI_EVAL_INPUT_BUFFER_SIGNATURE.
  • Set MethodName to 'ABCD' or MethodNameAsUlong to (ULONG)('DCBA').
For more information about how to use this structure, see Evaluating ACPI Control Methods.

Requirements

Requirement Value
Minimum supported client Windows 2000 and later versions of Windows.
Header acpiioct.h (include Acpiioct.h)

See also

IOCTL_ACPI_ASYNC_EVAL_METHOD

IOCTL_ACPI_EVAL_METHOD