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FLT_PARAMETERS for IRP_MJ_CREATE_MAILSLOT union

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The following structure within the FLT_PARAMETERS union is used when the MajorFunction field of the FLT_IO_PARAMETER_BLOCK structure is IRP_MJ_CREATE_MAILSLOT.

Syntax

typedef union _FLT_PARAMETERS {
  ...    ;
  struct {
    PIO_SECURITY_CONTEXT     SecurityContext;
    ULONG                    Options;
    USHORT POINTER_ALIGNMENT Reserved;
    USHORT                   ShareAccess;
    PVOID                    Parameters;
  } CreateMailslot;
  ...    ;
} FLT_PARAMETERS, *PFLT_PARAMETERS;

Members

The CreateMailslot structure of FLT_PARAMETERS contains the following members.

  • SecurityContext: Pointer to an IO_SECURITY_CONTEXT structure that represents the security context of an IRP_MJ_CREATE_MAILSLOT request, where:

  • SecurityContext->AccessState is a pointer to an ACCESS_STATE structure that contains the object's subject context, granted access types, and remaining desired access types.

  • SecurityContext->DesiredAccess is an ACCESS_MASK structure that specifies access rights requested for the mailslot. For more information, see the DesiredAccess parameter of FltCreateMailslotFile.

  • Options: Bitmask of flags that specify the options to be applied when creating or opening the mailslot, as well as the action to be taken if the mailslot already exists. The low 24 bits of this member correspond to the CreateOptions parameter for FltCreateMailslotFile. The high 8 bits correspond to the CreateDisposition parameter for FltCreateMailslotFile.

  • Reserved: Reserved; do not use.

  • ShareAccess: Bitmask of share access rights requested for the mailslot file. If this parameter is zero, exclusive access is being requested. For more information, see the ShareAccess parameter to FltCreateMailslotFile.

  • Parameters: Pointer to a MAILSLOT_CREATE_PARAMETERS structure containing information about the mailslot that is being created or opened.

Remarks

FLT_PARAMETERS contains a CreateMailslot structure when the I/O operation is IRP_MJ_CREATE_MAILSLOT. The I/O operation is represented by a FLT_CALLBACK_DATA structure, with the operation parameters contained within the FLT_IO_PARAMETER_BLOCK structure that the callback data's Iopb parameter points to.

A file system minifilter driver that has registered a callback routine for IRP_MJ_CREATE_MAILSLOT operations should perform any needed processing and return.

Note that, other than the last longword field, the fields in the CreateMailslot structure must match those for the Create structure.

IRP_MJ_CREATE_MAILSLOT is an IRP-based operation.

Requirements

Requirement type Requirement
Header Fltkernel.h (include Fltkernel.h)

See also

ACCESS_MASK

ACCESS_STATE

FLT_CALLBACK_DATA

FLT_IO_PARAMETER_BLOCK

FLT_PARAMETERS

FltCreateMailslotFile

IRP_MJ_CREATE_MAILSLOT

MAILSLOT_CREATE_PARAMETERS