DosFSCtl

DosFSCtl provides an extended standard interface between an application and an FSD.

DosFSCtl

(DataArea, DataLengthMax, DataLength, ParmList, ParmLengthMax, ParmLength, FunctionCode, RouteName, FileHandle, RouteMethod, Reserved)

DataArea (PBYTE) - input

Address of the data area.
DataLengthMax (USHORT) - input
The maximum length in bytes to be returned by the FSD in DataArea. DataLength may be longer than this on input, but not on output.
DataLength (PUSHORT) - input/output
Address of the length in bytes of data in DataArea. On input, it is the length of data being sent, and on output is the length of the data that was returned by the FSD. If ERROR_BUFFER_OVERFLOW is returned from the call, then it is the size of the buffer required to hold the data returned by the FSD.
ParmList (PBYTE) - input
Address of the command specific parameter list.
ParmLengthMax (USHORT) - input
The maximum length in bytes of the data to be returned by the FSD in ParmList. ParmLength may be longer than this on input, but not on output.
ParmLength (PUSHORT) - input/output
Address of, on input, the length in bytes of parameters passed in by the application, and on return it is the length of parameters returned by the FSD. If ERROR_BUFFER_OVERFLOW is returned from the call, then it is the size of the buffer required to hold the parameters returned by the FSD. No other data is returned in this case.
FunctionCode (USHORT) - input
The file system-specific function code. For remote FSDs, there are two kinds of possible FsCtl calls: FsCtl calls that are handled locally, and FsCtl calls that are exported across the network. If bit 0x4000 is set in the function code, then this indicates to the remote FSD that the function should be exported. The range of function codes are split up as follows: Function codes between 0x0000 and 0x7FFF are reserved for use by OS/2. Function codes between 0x8000 and 0xBFFF are FSD defined FsCtl functions handled by the local FSD. Function codes between 0xC000 and 0xFFFF are FSD defined FsCtl functions exported to the server.

FunctionCode = 1: returns FSD error code information. Error code is passed to the FSD in the first word of ParmList. On return, the first word of the Data area contains the length of the following ASCIIZ string. The ASCIIZ string begins at the second word and is an explanation of the error code.

RouteName (PSZ) - input
Address of the ASCIIZ name of the FSD, or the pathname of a file or directory the operation should apply to.
FileHandle (HFILE) - input
The file or device specific handle.
RouteMethod (USHORT) - input
Selects how the request is routed.

Value

Definition
1
FileHandle directs routing. RouteName must be a NUL pointer (0L). The FSD associated with the handle receives the request.
2
RouteMethod refers to a pathname, that directs routing. FileHandle must be -1. The FSD associated with the drive that the pathname refers to at the time of the request receives the request. The pathname need not refer to a file or directory that actually exists, only to a drive. A relative pathname may be used, it is processed like any other pathname.
3
RouteMethod refers to an FSD name, that directs routing. FileHandle must
be -1. The named FSD receives the request.
Reserved (ULONG) - input
Reserved, must be set to zero.
rc (USHORT) - return
Return code descriptions are:
• NO_ERROR
  
• ERROR_INVALID_FUNCTION
  
• ERROR_INVALID_HANDLE
  87
  ERROR_INVALID_PARAMETER
  95
  ERROR_INTERRUPT
  111
  ERROR_BUFFER_OVERFLOW
  117
  ERROR_INVALID_CATEGORY
  124
  ERROR_INVALID_LEVEL
  252
  ERROR_INVALID_FSD_NAME

  ---

  [Back: DosFSAttach]
  [Next: DosFSRamSemClear]