DosDevIOCtl - Parameters

hDevice (HFILE) - input

Device handle returned by DosOpen, or a standard (open) device handle.

category (ULONG) - input

Device category.

The valid range is 0 to 255.

function (ULONG) - input

Device-specific function code.

The valid range is 0 to 255.

pParams (PVOID) - input

Address of the command-specific argument list.

cbParmLenMax (ULONG) - input

Length, in bytes, of pParams.

This is the maximum length of the data to be returned in pParams. pcbParmLen may be larger than this on input, but not on output.

pcbParmLen (PULONG) - in/out

Pointer to the length of parameters.

Input

Pointer to the length, in bytes, of the parameters passed in pParams. by the application.
Output
Pointer to the length, in bytes, of the parameters returned.

If this function returns ERROR_BUFFER_OVERFLOW, then pcbParmLen points to the size of the buffer required to hold the parameters returned. No other data is returned in this case.

pData (PVOID) - input

Address of the data area.

cbDataLenMax (ULONG) - input

Length, in bytes, of pData.

This is the maximum length of the data to be returned in pData. pcbDataLen may be larger than this on input, but not on output.

pcbDataLen (PULONG) - in/out

Pointer to the length of data.

Input

Pointer to the length, in bytes, of the data passed by the application in pData.
Output
Pointer to the length, in bytes, of the data returned.

If this function returns ERROR_BUFFER_OVERFLOW, then pcbDataLen points to the size of the buffer required to hold the data returned.

ulrc (APIRET) - returns

Return Code.

DosDevIOCtl returns one of the following values:

• NO_ERROR 1
  ERROR_INVALID_FUNCTION
  6
  ERROR_INVALID_HANDLE
  15
  ERROR_INVALID_DRIVE
  31
  ERROR_GEN_FAILURE
  87
  ERROR_INVALID_PARAMETER
  111
  ERROR_BUFFER_OVERFLOW
  115
  ERROR_PROTECTION_VIOLATION
  117
  ERROR_INVALID_CATEGORY
  119
  ERROR_BAD_DRIVER_LEVEL
  163
  ERROR_UNCERTAIN_MEDIA
  165
  ERROR_MONITORS_NOT_SUPPORTED
  For a full list of error codes, see Errors.

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