#ifndef _NTIOAPI_H

// System calls

NTSYSCALLAPI
NTSTATUS
NTAPI
NtCreateFile(
    _Out_ PHANDLE FileHandle,
    _In_ ACCESS_MASK DesiredAccess,
    _In_ POBJECT_ATTRIBUTES ObjectAttributes,
    _Out_ PIO_STATUS_BLOCK IoStatusBlock,
    _In_opt_ PLARGE_INTEGER AllocationSize,
    _In_ ULONG FileAttributes,
    _In_ ULONG ShareAccess,
    _In_ ULONG CreateDisposition,
    _In_ ULONG CreateOptions,
    _In_reads_bytes_opt_(EaLength) PVOID EaBuffer,
    _In_ ULONG EaLength
    );

#endif
View code on GitHub

#ifndef _NTZWAPI_H

NTSYSCALLAPI
NTSTATUS
NTAPI
ZwCreateFile(
    _Out_ PHANDLE FileHandle,
    _In_ ACCESS_MASK DesiredAccess,
    _In_ POBJECT_ATTRIBUTES ObjectAttributes,
    _Out_ PIO_STATUS_BLOCK IoStatusBlock,
    _In_opt_ PLARGE_INTEGER AllocationSize,
    _In_ ULONG FileAttributes,
    _In_ ULONG ShareAccess,
    _In_ ULONG CreateDisposition,
    _In_ ULONG CreateOptions,
    _In_reads_bytes_opt_(EaLength) PVOID EaBuffer,
    _In_ ULONG EaLength
    );

#endif
View code on GitHub

This function is documented in Windows Driver Kit here and here.

(Available also in 2000 DDK.)

FileHandle

Result of call - HANDLE to File Object.

DesiredAccess

Access mask based on definitions in schema FILE_* from <WinNT.h>.

ObjectAttributes

Name of file to create (or open), optionally path in name string. You can also define root directory, security descriptor and attributes OBJ_CASE_INSENSITIVE and OBJ_INHERIT.

IoStatusBlock

Pointer to IO_STATUS_BLOCK structure, that receive final status of function call. Can be one of:

AllocationSize

File size after creation.

FileAttributes

Attributes for newly created file, as follows:

FILE_ATTRIBUTE_READONLY
FILE_ATTRIBUTE_HIDDEN
FILE_ATTRIBUTE_SYSTEM
FILE_ATTRIBUTE_ARCHIVE
FILE_ATTRIBUTE_NORMAL
FILE_ATTRIBUTE_TEMPORARY
FILE_ATTRIBUTE_OFFLINE
FILE_ATTRIBUTE_NOT_CONTENT_INDEXED

ShareAccess

Specifies share method for opened object. Can be set to zero or any combination of flags:

FILE_SHARE_READ
FILE_SHARE_WRITE
FILE_SHARE_DELETE

CreateDisposition

Specifies disposition how to create or open object and can be one of:

FILE_SUPERSEDE - If file exists, deletes it before creation of new one.
FILE_OPEN - Fails, if file not exists.
FILE_CREATE - Fails, if file exists.
FILE_OPEN_IF - If file exists, opens it. If not, creates new one and then open it.
FILE_OVERWRITE - If file not exists, create and open it. If exists, open them and reset content.
FILE_OVERWRITE_IF - As FILE_OVERWRITE, but fails if file not exists.

CreateOptions

Creation options.

EaBuffer

Buffer for Extended Attributes contains one or more of FILE_FULL_EA_INFORMATION structures.

EaLength

Length of EaBuffer.

Documented by

Tomasz Nowak

NtCreateFile - NtDoc