Adding upstream version 7.0.14-dfsg.upstream/7.0.14-dfsg

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 1833 insertions, 0 deletions

diff --git a/include/iprt/file.h b/include/iprt/file.h
new file mode 100644
index 00000000..c271498f
--- /dev/null
+++ b/include/iprt/file.h
@@ -0,0 +1,1833 @@
+/** @file
+ * IPRT - File I/O.
+ */
+
+/*
+ * Copyright (C) 2006-2023 Oracle and/or its affiliates.
+ *
+ * This file is part of VirtualBox base platform packages, as
+ * available from https://www.virtualbox.org.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation, in version 3 of the
+ * License.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, see <https://www.gnu.org/licenses>.
+ *
+ * The contents of this file may alternatively be used under the terms
+ * of the Common Development and Distribution License Version 1.0
+ * (CDDL), a copy of it is provided in the "COPYING.CDDL" file included
+ * in the VirtualBox distribution, in which case the provisions of the
+ * CDDL are applicable instead of those of the GPL.
+ *
+ * You may elect to license modified versions of this file under the
+ * terms and conditions of either the GPL or the CDDL or both.
+ *
+ * SPDX-License-Identifier: GPL-3.0-only OR CDDL-1.0
+ */
+
+#ifndef IPRT_INCLUDED_file_h
+#define IPRT_INCLUDED_file_h
+#ifndef RT_WITHOUT_PRAGMA_ONCE
+# pragma once
+#endif
+
+#include <iprt/cdefs.h>
+#include <iprt/types.h>
+#include <iprt/stdarg.h>
+#include <iprt/fs.h>
+#include <iprt/sg.h>
+
+RT_C_DECLS_BEGIN
+
+/** @defgroup grp_rt_fileio     RTFile - File I/O
+ * @ingroup grp_rt
+ * @{
+ */
+
+/** Platform specific text line break.
+ * @deprecated Use text I/O streams and '\\n'. See iprt/stream.h. */
+#if defined(RT_OS_OS2) || defined(RT_OS_WINDOWS)
+# define RTFILE_LINEFEED    "\r\n"
+#else
+# define RTFILE_LINEFEED    "\n"
+#endif
+
+/** Platform specific native standard input "handle". */
+#ifdef RT_OS_WINDOWS
+# define RTFILE_NATIVE_STDIN ((uint32_t)-10)
+#else
+# define RTFILE_NATIVE_STDIN 0
+#endif
+
+/** Platform specific native standard out "handle". */
+#ifdef RT_OS_WINDOWS
+# define RTFILE_NATIVE_STDOUT ((uint32_t)-11)
+#else
+# define RTFILE_NATIVE_STDOUT 1
+#endif
+
+/** Platform specific native standard error "handle". */
+#ifdef RT_OS_WINDOWS
+# define RTFILE_NATIVE_STDERR ((uint32_t)-12)
+#else
+# define RTFILE_NATIVE_STDERR 2
+#endif
+
+
+/**
+ * Checks if the specified file name exists and is a regular file.
+ *
+ * Symbolic links will be resolved.
+ *
+ * @returns true if it's a regular file, false if it isn't.
+ * @param   pszPath         The path to the file.
+ *
+ * @sa      RTDirExists, RTPathExists, RTSymlinkExists.
+ */
+RTDECL(bool) RTFileExists(const char *pszPath);
+
+/**
+ * Queries the size of a file, given the path to it.
+ *
+ * Symbolic links will be resolved.
+ *
+ * @returns IPRT status code.
+ * @param   pszPath         The path to the file.
+ * @param   pcbFile         Where to return the file size (bytes).
+ *
+ * @sa      RTFileQuerySize, RTPathQueryInfoEx.
+ */
+RTDECL(int) RTFileQuerySizeByPath(const char *pszPath, uint64_t *pcbFile);
+
+
+/** @name Open flags
+ * @{ */
+/** Attribute access only.
+ * @remarks Only accepted on windows, requires RTFILE_O_ACCESS_ATTR_MASK
+ *          to yield a non-zero result.  Otherwise, this is invalid. */
+#define RTFILE_O_ATTR_ONLY              UINT32_C(0x00000000)
+/** Open the file with read access. */
+#define RTFILE_O_READ                   UINT32_C(0x00000001)
+/** Open the file with write access. */
+#define RTFILE_O_WRITE                  UINT32_C(0x00000002)
+/** Open the file with read & write access. */
+#define RTFILE_O_READWRITE              UINT32_C(0x00000003)
+/** The file access mask.
+ * @remarks The value 0 is invalid, except for windows special case. */
+#define RTFILE_O_ACCESS_MASK            UINT32_C(0x00000003)
+
+/** Open file in APPEND mode, so all writes to the file handle will
+ * append data at the end of the file.
+ * @remarks It is ignored if write access is not requested, that is
+ *          RTFILE_O_WRITE is not set.
+ * @note    Behaviour of functions differ between hosts: See RTFileWriteAt, as
+ *          well as ticketref:19003 (RTFileSetSize). */
+#define RTFILE_O_APPEND                 UINT32_C(0x00000004)
+                                     /* UINT32_C(0x00000008) is unused atm. */
+
+/** Sharing mode: deny none. */
+#define RTFILE_O_DENY_NONE              UINT32_C(0x00000080)
+/** Sharing mode: deny read. */
+#define RTFILE_O_DENY_READ              UINT32_C(0x00000010)
+/** Sharing mode: deny write. */
+#define RTFILE_O_DENY_WRITE             UINT32_C(0x00000020)
+/** Sharing mode: deny read and write. */
+#define RTFILE_O_DENY_READWRITE         UINT32_C(0x00000030)
+/** Sharing mode: deny all. */
+#define RTFILE_O_DENY_ALL               RTFILE_O_DENY_READWRITE
+/** Sharing mode: do NOT deny delete (NT).
+ * @remarks This might not be implemented on all platforms, and will be
+ *          defaulted & ignored on those.
+ */
+#define RTFILE_O_DENY_NOT_DELETE        UINT32_C(0x00000040)
+/** Sharing mode mask. */
+#define RTFILE_O_DENY_MASK              UINT32_C(0x000000f0)
+
+/** Action: Open an existing file. */
+#define RTFILE_O_OPEN                   UINT32_C(0x00000700)
+/** Action: Create a new file or open an existing one. */
+#define RTFILE_O_OPEN_CREATE            UINT32_C(0x00000100)
+/** Action: Create a new a file. */
+#define RTFILE_O_CREATE                 UINT32_C(0x00000200)
+/** Action: Create a new file or replace an existing one. */
+#define RTFILE_O_CREATE_REPLACE         UINT32_C(0x00000300)
+/** Action mask. */
+#define RTFILE_O_ACTION_MASK            UINT32_C(0x00000700)
+
+/** Turns off indexing of files on Windows hosts, *CREATE* only.
+ * @remarks Window only. */
+#define RTFILE_O_NOT_CONTENT_INDEXED    UINT32_C(0x00000800)
+/** Truncate the file.
+ * @remarks This will not truncate files opened for read-only.
+ * @remarks The truncation doesn't have to be atomically, so anyone else opening
+ *          the file may be racing us. The caller is responsible for not causing
+ *          this race. */
+#define RTFILE_O_TRUNCATE               UINT32_C(0x00001000)
+/** Make the handle inheritable on RTProcessCreate(/exec). */
+#define RTFILE_O_INHERIT                UINT32_C(0x00002000)
+/** Open file in non-blocking mode - non-portable.
+ * @remarks This flag may not be supported on all platforms, in which case it's
+ *          considered an invalid parameter. */
+#define RTFILE_O_NON_BLOCK              UINT32_C(0x00004000)
+/** Write through directly to disk. Workaround to avoid iSCSI
+ * initiator deadlocks on Windows hosts.
+ * @remarks This might not be implemented on all platforms, and will be ignored
+ *          on those. */
+#define RTFILE_O_WRITE_THROUGH          UINT32_C(0x00008000)
+
+/** Attribute access: Attributes can be read if the file is being opened with
+ * read access, and can be written with write access. */
+#define RTFILE_O_ACCESS_ATTR_DEFAULT    UINT32_C(0x00000000)
+/** Attribute access: Attributes can be read.
+ * @remarks Windows only.  */
+#define RTFILE_O_ACCESS_ATTR_READ       UINT32_C(0x00010000)
+/** Attribute access: Attributes can be written.
+ * @remarks Windows only.  */
+#define RTFILE_O_ACCESS_ATTR_WRITE      UINT32_C(0x00020000)
+/** Attribute access: Attributes can be both read & written.
+ * @remarks Windows only.  */
+#define RTFILE_O_ACCESS_ATTR_READWRITE  UINT32_C(0x00030000)
+/** Attribute access: The file attributes access mask.
+ * @remarks Windows only.  */
+#define RTFILE_O_ACCESS_ATTR_MASK       UINT32_C(0x00030000)
+
+/** Open file for async I/O
+ * @remarks This flag may not be needed on all platforms, and will be ignored on
+ *          those. */
+#define RTFILE_O_ASYNC_IO               UINT32_C(0x00040000)
+
+/** Disables caching.
+ *
+ * Useful when using very big files which might bring the host I/O scheduler to
+ * its knees during high I/O load.
+ *
+ * @remarks This flag might impose restrictions
+ *          on the buffer alignment, start offset and/or transfer size.
+ *
+ *          On Linux the buffer needs to be aligned to the 512 sector
+ *          boundary.
+ *
+ *          On Windows the FILE_FLAG_NO_BUFFERING is used (see
+ *          http://msdn.microsoft.com/en-us/library/cc644950(VS.85).aspx ).
+ *          The buffer address, the transfer size and offset needs to be aligned
+ *          to the sector size of the volume.  Furthermore FILE_APPEND_DATA is
+ *          disabled.  To write beyond the size of file use RTFileSetSize prior
+ *          writing the data to the file.
+ *
+ *          This flag does not work on Solaris if the target filesystem is ZFS.
+ *          RTFileOpen will return an error with that configuration.  When used
+ *          with UFS the same alginment restrictions apply like Linux and
+ *          Windows.
+ *
+ * @remarks This might not be implemented on all platforms, and will be ignored
+ *          on those.
+ */
+#define RTFILE_O_NO_CACHE               UINT32_C(0x00080000)
+
+/** Don't allow symbolic links as part of the path.
+ * @remarks this flag is currently not implemented and will be ignored. */
+#define RTFILE_O_NO_SYMLINKS            UINT32_C(0x20000000)
+
+/** Unix file mode mask for use when creating files. */
+#define RTFILE_O_CREATE_MODE_MASK       UINT32_C(0x1ff00000)
+/** The number of bits to shift to get the file mode mask.
+ * To extract it: (fFlags & RTFILE_O_CREATE_MODE_MASK) >> RTFILE_O_CREATE_MODE_SHIFT.
+ */
+#define RTFILE_O_CREATE_MODE_SHIFT      20
+
+/** Temporary file that should be automatically deleted when closed.
+ * If not supported by the OS, the open call will fail with VERR_NOT_SUPPORTED
+ * to prevent leaving undeleted files behind.
+ * @note On unix the file wont be visible and cannot be accessed by it's path.
+ *       On Windows it will be visible but only accessible of deletion is
+ *       shared.  Not implemented on OS/2. */
+#define RTFILE_O_TEMP_AUTO_DELETE       UINT32_C(0x40000000)
+
+                                      /* UINT32_C(0x80000000) is unused atm. */
+
+/** Mask of all valid flags.
+ * @remark  This doesn't validate the access mode properly.
+ */
+#define RTFILE_O_VALID_MASK             UINT32_C(0x7ffffff7)
+
+/** @} */
+
+
+/** Action taken by RTFileOpenEx. */
+typedef enum RTFILEACTION
+{
+    /** Invalid zero value.   */
+    RTFILEACTION_INVALID = 0,
+    /** Existing file was opened (returned by RTFILE_O_OPEN and
+     * RTFILE_O_OPEN_CREATE). */
+    RTFILEACTION_OPENED,
+    /** New file was created (returned by RTFILE_O_CREATE and
+     * RTFILE_O_OPEN_CREATE). */
+    RTFILEACTION_CREATED,
+    /** Existing file was replaced (returned by RTFILE_O_CREATE_REPLACE). */
+    RTFILEACTION_REPLACED,
+    /** Existing file was truncated (returned if RTFILE_O_TRUNCATE take effect). */
+    RTFILEACTION_TRUNCATED,
+    /** The file already exists (returned by RTFILE_O_CREATE on failure). */
+    RTFILEACTION_ALREADY_EXISTS,
+    /** End of valid values. */
+    RTFILEACTION_END,
+    /** Type size hack.   */
+    RTFILEACTION_32BIT_HACK = 0x7fffffff
+} RTFILEACTION;
+/** Pointer to action taken value (RTFileOpenEx).    */
+typedef RTFILEACTION *PRTFILEACTION;
+
+
+#ifdef IN_RING3
+/**
+ * Force the use of open flags for all files opened after the setting is
+ * changed. The caller is responsible for not causing races with RTFileOpen().
+ *
+ * @returns iprt status code.
+ * @param   fOpenForAccess  Access mode to which the set/mask settings apply.
+ * @param   fSet            Open flags to be forced set.
+ * @param   fMask           Open flags to be masked out.
+ */
+RTR3DECL(int)  RTFileSetForceFlags(unsigned fOpenForAccess, unsigned fSet, unsigned fMask);
+#endif /* IN_RING3 */
+
+/**
+ * Open a file.
+ *
+ * @returns iprt status code.
+ * @param   pFile           Where to store the handle to the opened file.
+ * @param   pszFilename     Path to the file which is to be opened. (UTF-8)
+ * @param   fOpen           Open flags, i.e a combination of the RTFILE_O_* defines.
+ *                          The ACCESS, ACTION and DENY flags are mandatory!
+ */
+RTDECL(int)  RTFileOpen(PRTFILE pFile, const char *pszFilename, uint64_t fOpen);
+
+/**
+ * Open a file given as a format string.
+ *
+ * @returns iprt status code.
+ * @param   pFile           Where to store the handle to the opened file.
+ * @param   fOpen           Open flags, i.e a combination of the RTFILE_O_* defines.
+ *                          The ACCESS, ACTION and DENY flags are mandatory!
+ * @param   pszFilenameFmt  Format string givin the path to the file which is to
+ *                          be opened. (UTF-8)
+ * @param   ...             Arguments to the format string.
+ */
+RTDECL(int)  RTFileOpenF(PRTFILE pFile, uint64_t fOpen, const char *pszFilenameFmt, ...) RT_IPRT_FORMAT_ATTR(3, 4);
+
+/**
+ * Open a file given as a format string.
+ *
+ * @returns iprt status code.
+ * @param   pFile           Where to store the handle to the opened file.
+ * @param   fOpen           Open flags, i.e a combination of the RTFILE_O_* defines.
+ *                          The ACCESS, ACTION and DENY flags are mandatory!
+ * @param   pszFilenameFmt  Format string givin the path to the file which is to
+ *                          be opened. (UTF-8)
+ * @param   va              Arguments to the format string.
+ */
+RTDECL(int)  RTFileOpenV(PRTFILE pFile, uint64_t fOpen, const char *pszFilenameFmt, va_list va) RT_IPRT_FORMAT_ATTR(3, 0);
+
+/**
+ * Open a file, extended version.
+ *
+ * @returns iprt status code.
+ * @param   pszFilename     Path to the file which is to be opened. (UTF-8)
+ * @param   fOpen           Open flags, i.e a combination of the RTFILE_O_* defines.
+ *                          The ACCESS, ACTION and DENY flags are mandatory!
+ * @param   phFile          Where to store the handle to the opened file.
+ * @param   penmActionTaken Where to return an indicator of which action was
+ *                          taken.  This is optional and it is recommended to
+ *                          pass NULL when not strictly needed as it adds
+ *                          complexity (slower) on posix systems.
+ */
+RTDECL(int)  RTFileOpenEx(const char *pszFilename, uint64_t fOpen, PRTFILE phFile, PRTFILEACTION penmActionTaken);
+
+/**
+ * Open the bit bucket (aka /dev/null or nul).
+ *
+ * @returns IPRT status code.
+ * @param   phFile          Where to store the handle to the opened file.
+ * @param   fAccess         The desired access only, i.e. read, write or both.
+ */
+RTDECL(int)  RTFileOpenBitBucket(PRTFILE phFile, uint64_t fAccess);
+
+/**
+ * Duplicates a file handle.
+ *
+ * @returns IPRT status code.
+ * @param   hFileSrc        The handle to duplicate.
+ * @param   fFlags          RTFILE_O_INHERIT or zero.
+ * @param   phFileNew       Where to return the new file handle
+ */
+RTDECL(int)  RTFileDup(RTFILE hFileSrc, uint64_t fFlags, PRTFILE phFileNew);
+
+/**
+ * Close a file opened by RTFileOpen().
+ *
+ * @returns iprt status code.
+ * @param   File            The file handle to close.
+ */
+RTDECL(int)  RTFileClose(RTFILE File);
+
+/**
+ * Creates an IPRT file handle from a native one.
+ *
+ * @returns IPRT status code.
+ * @param   pFile           Where to store the IPRT file handle.
+ * @param   uNative         The native handle.
+ */
+RTDECL(int) RTFileFromNative(PRTFILE pFile, RTHCINTPTR uNative);
+
+/**
+ * Gets the native handle for an IPRT file handle.
+ *
+ * @return  The native handle.
+ * @param   File            The IPRT file handle.
+ */
+RTDECL(RTHCINTPTR) RTFileToNative(RTFILE File);
+
+/**
+ * Delete a file.
+ *
+ * @returns iprt status code.
+ * @param   pszFilename     Path to the file which is to be deleted. (UTF-8)
+ * @todo    This is a RTPath api!
+ */
+RTDECL(int)  RTFileDelete(const char *pszFilename);
+
+/** @name Seek flags.
+ * @{ */
+/** Seek from the start of the file. */
+#define RTFILE_SEEK_BEGIN     0x00
+/** Seek from the current file position. */
+#define RTFILE_SEEK_CURRENT   0x01
+/** Seek from the end of the file. */
+#define RTFILE_SEEK_END       0x02
+/** @internal */
+#define RTFILE_SEEK_FIRST     RTFILE_SEEK_BEGIN
+/** @internal */
+#define RTFILE_SEEK_LAST      RTFILE_SEEK_END
+/** @} */
+
+
+/**
+ * Changes the read & write position in a file.
+ *
+ * @returns iprt status code.
+ * @param   File        Handle to the file.
+ * @param   offSeek     Offset to seek.
+ * @param   uMethod     Seek method, i.e. one of the RTFILE_SEEK_* defines.
+ * @param   poffActual  Where to store the new file position.
+ *                      NULL is allowed.
+ */
+RTDECL(int)  RTFileSeek(RTFILE File, int64_t offSeek, unsigned uMethod, uint64_t *poffActual);
+
+/**
+ * Read bytes from a file.
+ *
+ * @returns iprt status code.
+ * @param   File        Handle to the file.
+ * @param   pvBuf       Where to put the bytes we read.
+ * @param   cbToRead    How much to read.
+ * @param   pcbRead     How much we actually read .
+ *                      If NULL an error will be returned for a partial read.
+ */
+RTDECL(int)  RTFileRead(RTFILE File, void *pvBuf, size_t cbToRead, size_t *pcbRead);
+
+/**
+ * Read bytes from a file at a given offset.
+ *
+ * @returns iprt status code.
+ * @param   File        Handle to the file.
+ * @param   off         Where to read.
+ * @param   pvBuf       Where to put the bytes we read.
+ * @param   cbToRead    How much to read.
+ * @param   pcbRead     How much we actually read .
+ *                      If NULL an error will be returned for a partial read.
+ *
+ * @note    OS/2 requires separate seek and write calls.
+ *
+ * @note    Whether the file position is modified or not is host specific.
+ */
+RTDECL(int)  RTFileReadAt(RTFILE File, RTFOFF off, void *pvBuf, size_t cbToRead, size_t *pcbRead);
+
+/**
+ * Read bytes from a file at a given offset into a S/G buffer.
+ *
+ * @returns iprt status code.
+ * @param   hFile       Handle to the file.
+ * @param   pSgBuf      Pointer to the S/G buffer to read into.
+ * @param   cbToRead    How much to read.
+ * @param   pcbRead     How much we actually read .
+ *                      If NULL an error will be returned for a partial read.
+ *
+ * @note    It is not possible to guarantee atomicity on all platforms, so
+ *          caller must take care wrt concurrent access to @a hFile.
+ */
+RTDECL(int)  RTFileSgRead(RTFILE hFile, PRTSGBUF pSgBuf, size_t cbToRead, size_t *pcbRead);
+
+/**
+ * Read bytes from a file at a given offset into a S/G buffer.
+ *
+ * @returns iprt status code.
+ * @param   hFile       Handle to the file.
+ * @param   off         Where to read.
+ * @param   pSgBuf      Pointer to the S/G buffer to read into.
+ * @param   cbToRead    How much to read.
+ * @param   pcbRead     How much we actually read .
+ *                      If NULL an error will be returned for a partial read.
+ *
+ * @note    Whether the file position is modified or not is host specific.
+ *
+ * @note    It is not possible to guarantee atomicity on all platforms, so
+ *          caller must take care wrt concurrent access to @a hFile.
+ */
+RTDECL(int)  RTFileSgReadAt(RTFILE hFile, RTFOFF off, PRTSGBUF pSgBuf, size_t cbToRead, size_t *pcbRead);
+
+/**
+ * Write bytes to a file.
+ *
+ * @returns iprt status code.
+ * @param   File        Handle to the file.
+ * @param   pvBuf       What to write.
+ * @param   cbToWrite   How much to write.
+ * @param   pcbWritten  How much we actually wrote.
+ *                      If NULL an error will be returned for a partial write.
+ */
+RTDECL(int)  RTFileWrite(RTFILE File, const void *pvBuf, size_t cbToWrite, size_t *pcbWritten);
+
+/**
+ * Write bytes to a file at a given offset.
+ *
+ * @returns iprt status code.
+ * @param   hFile       Handle to the file.
+ * @param   off         Where to write.
+ * @param   pvBuf       What to write.
+ * @param   cbToWrite   How much to write.
+ * @param   pcbWritten  How much we actually wrote.
+ *                      If NULL an error will be returned for a partial write.
+ *
+ * @note    OS/2 requires separate seek and write calls.
+ *
+ * @note    Whether the file position is modified or not is host specific.
+ *
+ * @note    Whether @a off is used when @a hFile was opened with RTFILE_O_APPEND
+ *          is also host specific.  Currently Linux is the the only one
+ *          documented to ignore @a off.
+ */
+RTDECL(int)  RTFileWriteAt(RTFILE hFile, RTFOFF off, const void *pvBuf, size_t cbToWrite, size_t *pcbWritten);
+
+/**
+ * Write bytes from a S/G buffer to a file.
+ *
+ * @returns iprt status code.
+ * @param   hFile       Handle to the file.
+ * @param   pSgBuf      What to write.
+ * @param   cbToWrite   How much to write.
+ * @param   pcbWritten  How much we actually wrote.
+ *                      If NULL an error will be returned for a partial write.
+ *
+ * @note    It is not possible to guarantee atomicity on all platforms, so
+ *          caller must take care wrt concurrent access to @a hFile.
+ */
+RTDECL(int)  RTFileSgWrite(RTFILE hFile, PRTSGBUF pSgBuf, size_t cbToWrite, size_t *pcbWritten);
+
+/**
+ * Write bytes from a S/G buffer to a file at a given offset.
+ *
+ * @returns iprt status code.
+ * @param   hFile       Handle to the file.
+ * @param   off         Where to write.
+ * @param   pSgBuf      What to write.
+ * @param   cbToWrite   How much to write.
+ * @param   pcbWritten  How much we actually wrote.
+ *                      If NULL an error will be returned for a partial write.
+ *
+ * @note    It is not possible to guarantee atomicity on all platforms, so
+ *          caller must take care wrt concurrent access to @a hFile.
+ *
+ * @note    Whether the file position is modified or not is host specific.
+ *
+ * @note    Whether @a off is used when @a hFile was opened with RTFILE_O_APPEND
+ *          is also host specific.  Currently Linux is the the only one
+ *          documented to ignore @a off.
+ */
+RTDECL(int)  RTFileSgWriteAt(RTFILE hFile, RTFOFF off, PRTSGBUF pSgBuf, size_t cbToWrite, size_t *pcbWritten);
+
+/**
+ * Flushes the buffers for the specified file.
+ *
+ * @returns iprt status code.
+ * @retval  VINF_NOT_SUPPORTED if it is a special file that does not support
+ *          flushing.  This is reported as a informational status since in most
+ *          cases this is entirely harmless (e.g. tty) and simplifies the usage.
+ * @param   File        Handle to the file.
+ */
+RTDECL(int)  RTFileFlush(RTFILE File);
+
+/**
+ * Set the size of the file.
+ *
+ * @returns iprt status code.
+ * @param   File        Handle to the file.
+ * @param   cbSize      The new file size.
+ */
+RTDECL(int)  RTFileSetSize(RTFILE File, uint64_t cbSize);
+
+/**
+ * Query the size of the file.
+ *
+ * @returns iprt status code.
+ * @param   File        Handle to the file.
+ * @param   pcbSize     Where to store the filesize.
+ */
+RTDECL(int)  RTFileQuerySize(RTFILE File, uint64_t *pcbSize);
+
+/**
+ * Determine the maximum file size.
+ *
+ * @returns The max size of the file.
+ *          -1 on failure, the file position is undefined.
+ * @param   File        Handle to the file.
+ * @see     RTFileQueryMaxSizeEx.
+ */
+RTDECL(RTFOFF) RTFileGetMaxSize(RTFILE File);
+
+/**
+ * Determine the maximum file size.
+ *
+ * @returns IPRT status code.
+ * @param   File        Handle to the file.
+ * @param   pcbMax      Where to store the max file size.
+ * @see     RTFileGetMaxSize.
+ */
+RTDECL(int) RTFileQueryMaxSizeEx(RTFILE File, PRTFOFF pcbMax);
+
+/**
+ * Queries the sector size (/ logical block size) for a disk or similar.
+ *
+ * @returns IPRT status code.
+ * @retval  VERR_INVALID_FUNCTION if not a disk/similar.  Could also be returned
+ *          if not really implemented.
+ * @param   hFile       Handle to the disk.  This must typically be a device
+ *                      rather than a file or directory, though this may vary
+ *                      from OS to OS.
+ * @param   pcbSector   Where to store the sector size.
+ */
+RTDECL(int) RTFileQuerySectorSize(RTFILE hFile, uint32_t *pcbSector);
+
+/**
+ * Gets the current file position.
+ *
+ * @returns File offset.
+ * @returns ~0UUL on failure.
+ * @param   File        Handle to the file.
+ */
+RTDECL(uint64_t)  RTFileTell(RTFILE File);
+
+/**
+ * Checks if the supplied handle is valid.
+ *
+ * @returns true if valid.
+ * @returns false if invalid.
+ * @param   File        The file handle
+ */
+RTDECL(bool) RTFileIsValid(RTFILE File);
+
+/**
+ * Copies a file.
+ *
+ * @returns IPRT status code
+ * @retval VERR_ALREADY_EXISTS if the destination file exists.
+ *
+ * @param   pszSrc      The path to the source file.
+ * @param   pszDst      The path to the destination file.
+ *                      This file will be created.
+ */
+RTDECL(int) RTFileCopy(const char *pszSrc, const char *pszDst);
+
+/**
+ * Copies a file given the handles to both files.
+ *
+ * @returns IPRT status code
+ *
+ * @param   FileSrc     The source file. The file position is unaltered.
+ * @param   FileDst     The destination file.
+ *                      On successful returns the file position is at the end of the file.
+ *                      On failures the file position and size is undefined.
+ */
+RTDECL(int) RTFileCopyByHandles(RTFILE FileSrc, RTFILE FileDst);
+
+/** Flags for RTFileCopyEx().
+ * @{ */
+/** Do not use RTFILE_O_DENY_WRITE on the source file to allow for copying files opened for writing. */
+#define RTFILECOPY_FLAGS_NO_SRC_DENY_WRITE  RT_BIT(0)
+/** Do not use RTFILE_O_DENY_WRITE on the target file. */
+#define RTFILECOPY_FLAGS_NO_DST_DENY_WRITE  RT_BIT(1)
+/** Do not use RTFILE_O_DENY_WRITE on either of the two files. */
+#define RTFILECOPY_FLAGS_NO_DENY_WRITE      ( RTFILECOPY_FLAGS_NO_SRC_DENY_WRITE | RTFILECOPY_FLAGS_NO_DST_DENY_WRITE )
+/** */
+#define RTFILECOPY_FLAGS_MASK               UINT32_C(0x00000003)
+/** @} */
+
+/**
+ * Copies a file.
+ *
+ * @returns IPRT status code
+ * @retval  VERR_ALREADY_EXISTS if the destination file exists.
+ *
+ * @param   pszSrc      The path to the source file.
+ * @param   pszDst      The path to the destination file.
+ *                      This file will be created.
+ * @param   fFlags      Flags (RTFILECOPY_*).
+ * @param   pfnProgress Pointer to callback function for reporting progress.
+ * @param   pvUser      User argument to pass to pfnProgress along with the completion percentage.
+ */
+RTDECL(int) RTFileCopyEx(const char *pszSrc, const char *pszDst, uint32_t fFlags, PFNRTPROGRESS pfnProgress, void *pvUser);
+
+/**
+ * Copies a file given the handles to both files and
+ * provide progress callbacks.
+ *
+ * @returns IPRT status code.
+ *
+ * @param   FileSrc     The source file. The file position is unaltered.
+ * @param   FileDst     The destination file.
+ *                      On successful returns the file position is at the end of the file.
+ *                      On failures the file position and size is undefined.
+ * @param   pfnProgress Pointer to callback function for reporting progress.
+ * @param   pvUser      User argument to pass to pfnProgress along with the completion percentage.
+ */
+RTDECL(int) RTFileCopyByHandlesEx(RTFILE FileSrc, RTFILE FileDst, PFNRTPROGRESS pfnProgress, void *pvUser);
+
+/**
+ * Copies a part of a file to another one.
+ *
+ * @returns IPRT status code.
+ * @retval  VERR_EOF if @a pcbCopied is NULL and the end-of-file is reached
+ *          before @a cbToCopy bytes have been copied.
+ *
+ * @param   hFileSrc    Handle to the source file.  Must be readable.
+ * @param   offSrc      The source file offset.
+ * @param   hFileDst    Handle to the destination file.  Must be writable and
+ *                      RTFILE_O_APPEND must be be in effect.
+ * @param   offDst      The destination file offset.
+ * @param   cbToCopy    How many bytes to copy.
+ * @param   fFlags      Reserved for the future, must be zero.
+ * @param   pcbCopied   Where to return the exact number of bytes copied.
+ *                      Optional.
+ *
+ * @note    The file positions of @a hFileSrc and @a hFileDst are undefined
+ *          upon return of this function.
+ *
+ * @sa      RTFileCopyPartEx.
+ */
+RTDECL(int) RTFileCopyPart(RTFILE hFileSrc, RTFOFF offSrc, RTFILE hFileDst, RTFOFF offDst, uint64_t cbToCopy,
+                           uint32_t fFlags, uint64_t *pcbCopied);
+
+
+/** Copy buffer state for RTFileCopyPartEx.
+ * @note The fields are considered internal!
+ */
+typedef struct RTFILECOPYPARTBUFSTATE
+{
+    /** Magic value (RTFILECOPYPARTBUFSTATE_MAGIC).
+     * @internal */
+    uint32_t    uMagic;
+    /** Allocation type (internal).
+     * @internal */
+    int32_t     iAllocType;
+    /** Buffer pointer.
+     * @internal */
+    uint8_t    *pbBuf;
+    /** Buffer size.
+     * @internal */
+    size_t      cbBuf;
+    /** Reserved.
+     * @internal */
+    void       *papReserved[3];
+} RTFILECOPYPARTBUFSTATE;
+/** Pointer to copy buffer state for RTFileCopyPartEx(). */
+typedef RTFILECOPYPARTBUFSTATE *PRTFILECOPYPARTBUFSTATE;
+/** Magic value for the RTFileCopyPartEx() buffer state structure (Stephen John Fry). */
+#define RTFILECOPYPARTBUFSTATE_MAGIC   UINT32_C(0x19570857)
+
+/**
+ * Prepares buffer state for one or more RTFileCopyPartEx() calls.
+ *
+ * Caller must call RTFileCopyPartCleanup() after the final RTFileCopyPartEx()
+ * call.
+ *
+ * @returns IPRT status code.
+ * @param   pBufState   The buffer state to prepare.
+ * @param   cbToCopy    The number of bytes we typically to copy in one
+ *                      RTFileCopyPartEx call.
+ */
+RTDECL(int) RTFileCopyPartPrep(PRTFILECOPYPARTBUFSTATE pBufState, uint64_t cbToCopy);
+
+/**
+ * Cleans up after RTFileCopyPartPrep() once the final RTFileCopyPartEx()
+ * call has been made.
+ *
+ * @param   pBufState   The buffer state to clean up.
+ */
+RTDECL(void) RTFileCopyPartCleanup(PRTFILECOPYPARTBUFSTATE pBufState);
+
+/**
+ * Copies a part of a file to another one, extended version.
+ *
+ * @returns IPRT status code.
+ * @retval  VERR_EOF if @a pcbCopied is NULL and the end-of-file is reached
+ *          before @a cbToCopy bytes have been copied.
+ *
+ * @param   hFileSrc    Handle to the source file.  Must be readable.
+ * @param   offSrc      The source file offset.
+ * @param   hFileDst    Handle to the destination file.  Must be writable and
+ *                      RTFILE_O_APPEND must be be in effect.
+ * @param   offDst      The destination file offset.
+ * @param   cbToCopy    How many bytes to copy.
+ * @param   fFlags      Reserved for the future, must be zero.
+ * @param   pBufState   Copy buffer state prepared by RTFileCopyPartPrep().
+ * @param   pcbCopied   Where to return the exact number of bytes copied.
+ *                      Optional.
+ *
+ * @note    The file positions of @a hFileSrc and @a hFileDst are undefined
+ *          upon return of this function.
+ *
+ * @sa      RTFileCopyPart.
+ */
+RTDECL(int) RTFileCopyPartEx(RTFILE hFileSrc, RTFOFF offSrc, RTFILE hFileDst, RTFOFF offDst, uint64_t cbToCopy,
+                             uint32_t fFlags, PRTFILECOPYPARTBUFSTATE pBufState, uint64_t *pcbCopied);
+
+/**
+ * Copy file attributes from @a hFileSrc to @a hFileDst.
+ *
+ * @returns IPRT status code.
+ * @param   hFileSrc    Handle to the source file.
+ * @param   hFileDst    Handle to the destination file.
+ * @param   fFlags      Reserved, pass zero.
+ */
+RTDECL(int) RTFileCopyAttributes(RTFILE hFileSrc, RTFILE hFileDst, uint32_t fFlags);
+
+/**
+ * Compares two file given the paths to both files.
+ *
+ * @returns IPRT status code.
+ * @retval  VINF_SUCCESS if equal.
+ * @retval  VERR_NOT_EQUAL if not equal.
+ *
+ * @param   pszFile1    The path to the first file.
+ * @param   pszFile2    The path to the second file.
+ */
+RTDECL(int) RTFileCompare(const char *pszFile1, const char *pszFile2);
+
+/**
+ * Compares two file given the handles to both files.
+ *
+ * @returns IPRT status code.
+ * @retval  VINF_SUCCESS if equal.
+ * @retval  VERR_NOT_EQUAL if not equal.
+ *
+ * @param   hFile1      The first file.  Undefined return position.
+ * @param   hFile2      The second file.  Undefined return position.
+ */
+RTDECL(int) RTFileCompareByHandles(RTFILE hFile1, RTFILE hFile2);
+
+/** Flags for RTFileCompareEx().
+ * @{ */
+/** Do not use RTFILE_O_DENY_WRITE on the first file. */
+#define RTFILECOMP_FLAGS_NO_DENY_WRITE_FILE1  RT_BIT(0)
+/** Do not use RTFILE_O_DENY_WRITE on the second file. */
+#define RTFILECOMP_FLAGS_NO_DENY_WRITE_FILE2  RT_BIT(1)
+/** Do not use RTFILE_O_DENY_WRITE on either of the two files. */
+#define RTFILECOMP_FLAGS_NO_DENY_WRITE      ( RTFILECOMP_FLAGS_NO_DENY_WRITE_FILE1 | RTFILECOMP_FLAGS_NO_DENY_WRITE_FILE2 )
+/** */
+#define RTFILECOMP_FLAGS_MASK               UINT32_C(0x00000003)
+/** @} */
+
+/**
+ * Compares two files, extended version with progress callback.
+ *
+ * @returns IPRT status code.
+ * @retval  VINF_SUCCESS if equal.
+ * @retval  VERR_NOT_EQUAL if not equal.
+ *
+ * @param   pszFile1    The path to the source file.
+ * @param   pszFile2    The path to the destination file. This file will be
+ *                      created.
+ * @param   fFlags      Flags, any of the RTFILECOMP_FLAGS_ \#defines.
+ * @param   pfnProgress Pointer to callback function for reporting progress.
+ * @param   pvUser      User argument to pass to pfnProgress along with the completion percentage.
+ */
+RTDECL(int) RTFileCompareEx(const char *pszFile1, const char *pszFile2, uint32_t fFlags, PFNRTPROGRESS pfnProgress, void *pvUser);
+
+/**
+ * Compares two files given their handles, extended version with progress
+ * callback.
+ *
+ * @returns IPRT status code.
+ * @retval  VINF_SUCCESS if equal.
+ * @retval  VERR_NOT_EQUAL if not equal.
+ *
+ * @param   hFile1      The first file.  Undefined return position.
+ * @param   hFile2      The second file.  Undefined return position.
+ *
+ * @param   fFlags      Flags, any of the RTFILECOMP_FLAGS_ \#defines, flags
+ *                      related to opening of the files will be ignored.
+ * @param   pfnProgress Pointer to callback function for reporting progress.
+ * @param   pvUser      User argument to pass to pfnProgress along with the completion percentage.
+ */
+RTDECL(int) RTFileCompareByHandlesEx(RTFILE hFile1, RTFILE hFile2, uint32_t fFlags, PFNRTPROGRESS pfnProgress, void *pvUser);
+
+/**
+ * Renames a file.
+ *
+ * Identical to RTPathRename except that it will ensure that the source is not a directory.
+ *
+ * @returns IPRT status code.
+ * @returns VERR_ALREADY_EXISTS if the destination file exists.
+ *
+ * @param   pszSrc      The path to the source file.
+ * @param   pszDst      The path to the destination file.
+ *                      This file will be created.
+ * @param   fRename     See RTPathRename.
+ */
+RTDECL(int) RTFileRename(const char *pszSrc, const char *pszDst, unsigned fRename);
+
+
+/** @name RTFileMove flags (bit masks).
+ * @{ */
+/** Replace destination file if present. */
+#define RTFILEMOVE_FLAGS_REPLACE      0x1
+/** Don't allow symbolic links as part of the path.
+ * @remarks this flag is currently not implemented and will be ignored. */
+#define RTFILEMOVE_FLAGS_NO_SYMLINKS  0x2
+/** @} */
+
+/**
+ * Converts file opening modes (used by fopen, for example) to IPRT
+ * compatible flags, which then can be used with RTFileOpen* APIs.
+ *
+ * @note    Handling sharing modes is not supported yet, so RTFILE_O_DENY_NONE
+ *          will always be used.
+ *
+ * @return  IPRT status code.
+ * @param   pszMode                 Mode string to convert.
+ * @param   pfMode                  Where to store the converted mode flags on
+ *                                  success.
+ */
+RTDECL(int) RTFileModeToFlags(const char *pszMode, uint64_t *pfMode);
+
+/**
+ * Converts file opening modes along with a separate disposition command
+ * to IPRT compatible flags, which then can be used with RTFileOpen* APIs.
+ *
+ * Access modes:
+ *      - "r":  Opens a file for reading.
+ *      - "r+": Opens a file for reading and writing.
+ *      - "w":  Opens a file for writing.
+ *      - "w+": Opens a file for writing and reading.
+ *
+ * Disposition modes:
+ *      - "oe", "open": Opens an existing file or fail if it does not exist.
+ *      - "oc", "open-create": Opens an existing file or create it if it does
+ *        not exist.
+ *      - "oa", "open-append": Opens an existing file and places the file
+ *        pointer at the end of the file, if opened with write access. Create
+ *        the file if it does not exist.
+ *      - "ot", "open-truncate": Opens and truncate an existing file or fail if
+ *        it does not exist.
+ *      - "ce", "create": Creates a new file if it does not exist. Fail if
+ *        exist.
+ *      - "ca", "create-replace": Creates a new file, always. Overwrites an
+ *        existing file.
+ *
+ * Sharing mode:
+ *      - "nr":     Deny read.
+ *      - "nw":     Deny write.
+ *      - "nrw":    Deny both read and write.
+ *      - "d":      Allow delete.
+ *      - "", NULL: Deny none, except delete.
+ *
+ * @return  IPRT status code.
+ * @param   pszAccess       Access mode string to convert.
+ * @param   pszDisposition  Disposition mode string to convert.
+ * @param   pszSharing      Sharing mode string to convert.
+ * @param   pfMode          Where to store the converted mode flags on success.
+ */
+RTDECL(int) RTFileModeToFlagsEx(const char *pszAccess, const char *pszDisposition, const char *pszSharing, uint64_t *pfMode);
+
+/**
+ * Moves a file.
+ *
+ * RTFileMove differs from RTFileRename in that it works across volumes.
+ *
+ * @returns IPRT status code.
+ * @returns VERR_ALREADY_EXISTS if the destination file exists.
+ *
+ * @param   pszSrc      The path to the source file.
+ * @param   pszDst      The path to the destination file.
+ *                      This file will be created.
+ * @param   fMove       A combination of the RTFILEMOVE_* flags.
+ */
+RTDECL(int) RTFileMove(const char *pszSrc, const char *pszDst, unsigned fMove);
+
+
+/**
+ * Creates a new file with a unique name using the given template, returning a
+ * handle to it.
+ *
+ * One or more trailing X'es in the template will be replaced by random alpha
+ * numeric characters until a RTFileOpen with RTFILE_O_CREATE succeeds or we
+ * run out of patience.
+ * For instance:
+ *          "/tmp/myprog-XXXXXX"
+ *
+ * As an alternative to trailing X'es, it is possible to put 3 or more X'es
+ * somewhere inside the file name. In the following string only the last
+ * bunch of X'es will be modified:
+ *          "/tmp/myprog-XXX-XXX.tmp"
+ *
+ * @returns IPRT status code.
+ * @param   phFile          Where to return the file handle on success.  Set to
+ *                          NIL on failure.
+ * @param   pszTemplate     The file name template on input. The actual file
+ *                          name on success. Empty string on failure.
+ * @param   fOpen           The RTFILE_O_XXX flags to open the file with.
+ *                          RTFILE_O_CREATE is mandatory.
+ * @see     RTFileCreateTemp
+ */
+RTDECL(int) RTFileCreateUnique(PRTFILE phFile, char *pszTemplate, uint64_t fOpen);
+
+/**
+ * Creates a new file with a unique name using the given template.
+ *
+ * One or more trailing X'es in the template will be replaced by random alpha
+ * numeric characters until a RTFileOpen with RTFILE_O_CREATE succeeds or we
+ * run out of patience.
+ * For instance:
+ *          "/tmp/myprog-XXXXXX"
+ *
+ * As an alternative to trailing X'es, it is possible to put 3 or more X'es
+ * somewhere inside the file name. In the following string only the last
+ * bunch of X'es will be modified:
+ *          "/tmp/myprog-XXX-XXX.tmp"
+ *
+ * @returns iprt status code.
+ * @param   pszTemplate     The file name template on input. The actual file
+ *                          name on success. Empty string on failure.
+ * @param   fMode           The mode to create the file with.  Use 0600 unless
+ *                          you have reason not to.
+ * @see     RTFileCreateUnique
+ */
+RTDECL(int) RTFileCreateTemp(char *pszTemplate, RTFMODE fMode);
+
+/**
+ * Secure version of @a RTFileCreateTemp with a fixed mode of 0600.
+ *
+ * This function behaves in the same way as @a RTFileCreateTemp with two
+ * additional points.  Firstly the mode is fixed to 0600.  Secondly it will
+ * fail if it is not possible to perform the operation securely.  Possible
+ * reasons include that the file could be removed by another unprivileged
+ * user before it is used (e.g. if is created in a non-sticky /tmp directory)
+ * or that the path contains symbolic links which another unprivileged user
+ * could manipulate; however the exact criteria will be specified on a
+ * platform-by-platform basis as platform support is added.
+ * @see RTPathIsSecure for the current list of criteria.
+ *
+ * @returns iprt status code.
+ * @returns VERR_NOT_SUPPORTED if the interface can not be supported on the
+ *                             current platform at this time.
+ * @returns VERR_INSECURE      if the file could not be created securely.
+ * @param   pszTemplate        The file name template on input. The actual
+ *                             file name on success. Empty string on failure.
+ * @see     RTFileCreateUnique
+ */
+RTDECL(int) RTFileCreateTempSecure(char *pszTemplate);
+
+/**
+ * Opens a new file with a unique name in the temp directory.
+ *
+ * Unlike the other temp file creation APIs, this does not allow you any control
+ * over the name.  Nor do you have to figure out where the temporary directory
+ * is.
+ *
+ * @returns iprt status code.
+ * @param   phFile          Where to return the handle to the file.
+ * @param   pszFilename     Where to return the name (+path) of the file .
+ * @param   cbFilename      The size of the buffer @a pszFilename points to.
+ * @param   fOpen           The RTFILE_O_XXX flags to open the file with.
+ *
+ * @remarks If actual control over the filename or location is required, we'll
+ *          create an extended edition of this API.
+ */
+RTDECL(int) RTFileOpenTemp(PRTFILE phFile, char *pszFilename, size_t cbFilename, uint64_t fOpen);
+
+
+/** @defgroup   grp_rt_fileio_locking   RT File locking API
+ *
+ * File locking general rules:
+ *
+ * Region to lock or unlock can be located beyond the end of file, this can be used for
+ * growing files.
+ * Read (or Shared) locks can be acquired held by an unlimited number of processes at the
+ * same time, but a Write (or Exclusive) lock can only be acquired by one process, and
+ * cannot coexist with a Shared lock. To acquire a Read lock, a process must wait until
+ * there are no processes holding any Write locks. To acquire a Write lock, a process must
+ * wait until there are no processes holding either kind of lock.
+ * By default, RTFileLock and RTFileChangeLock calls returns error immediately if the lock
+ * can't be acquired due to conflict with other locks, however they can be called in wait mode.
+ *
+ * Differences in implementation:
+ *
+ * Win32, OS/2: Locking is mandatory, since locks are enforced by the operating system.
+ * I.e. when file region is locked in Read mode, any write in it will fail; in case of Write
+ * lock - region can be read and writed only by lock's owner.
+ *
+ * Win32: File size change (RTFileSetSize) is not controlled by locking at all (!) in the
+ * operation system. Also see comments to RTFileChangeLock API call.
+ *
+ * Linux/Posix: By default locks in Unixes are advisory. This means that cooperating processes
+ * may use locks to coordinate access to a file between themselves, but programs are also free
+ * to ignore locks and access the file in any way they choose to.
+ *
+ * Additional reading:
+ *     - http://en.wikipedia.org/wiki/File_locking
+ *     - http://unixhelp.ed.ac.uk/CGI/man-cgi?fcntl+2
+ *     - http://msdn.microsoft.com/library/default.asp?url=/library/en-us/fileio/fs/lockfileex.asp
+ *
+ * @{
+ */
+
+/** @name Lock flags (bit masks).
+ * @{ */
+/** Read access, can be shared with others. */
+#define RTFILE_LOCK_READ            0x00
+/** Write access, one at a time. */
+#define RTFILE_LOCK_WRITE           0x01
+/** Don't wait for other locks to be released. */
+#define RTFILE_LOCK_IMMEDIATELY     0x00
+/** Wait till conflicting locks have been released. */
+#define RTFILE_LOCK_WAIT            0x02
+/** Valid flags mask */
+#define RTFILE_LOCK_MASK            0x03
+/** @} */
+
+
+/**
+ * Locks a region of file for read (shared) or write (exclusive) access.
+ *
+ * @returns iprt status code.
+ * @returns VERR_FILE_LOCK_VIOLATION if lock can't be acquired.
+ * @param   File        Handle to the file.
+ * @param   fLock       Lock method and flags, see RTFILE_LOCK_* defines.
+ * @param   offLock     Offset of lock start.
+ * @param   cbLock      Length of region to lock, may overlap the end of file.
+ */
+RTDECL(int)  RTFileLock(RTFILE File, unsigned fLock, int64_t offLock, uint64_t cbLock);
+
+/**
+ * Changes a lock type from read to write or from write to read.
+ *
+ * The region to type change must correspond exactly to an existing locked region.
+ * If change can't be done due to locking conflict and non-blocking mode is used, error is
+ * returned and lock keeps its state (see next warning).
+ *
+ * WARNING: win32 implementation of this call is not atomic, it transforms to a pair of
+ * calls RTFileUnlock and RTFileLock. Potentially the previously acquired lock can be
+ * lost, i.e. function is called in non-blocking mode, previous lock is freed, new lock can't
+ * be acquired, and old lock (previous state) can't be acquired back too. This situation
+ * may occurs _only_ if the other process is acquiring a _write_ lock in blocking mode or
+ * in race condition with the current call.
+ * In this very bad case special error code VERR_FILE_LOCK_LOST will be returned.
+ *
+ * @returns iprt status code.
+ * @returns VERR_FILE_NOT_LOCKED if region was not locked.
+ * @returns VERR_FILE_LOCK_VIOLATION if lock type can't be changed, lock remains its type.
+ * @returns VERR_FILE_LOCK_LOST if lock was lost, we haven't this lock anymore :(
+ * @param   File        Handle to the file.
+ * @param   fLock       Lock method and flags, see RTFILE_LOCK_* defines.
+ * @param   offLock     Offset of lock start.
+ * @param   cbLock      Length of region to lock, may overlap the end of file.
+ */
+RTDECL(int)  RTFileChangeLock(RTFILE File, unsigned fLock, int64_t offLock, uint64_t cbLock);
+
+/**
+ * Unlocks previously locked region of file.
+ * The region to unlock must correspond exactly to an existing locked region.
+ *
+ * @returns iprt status code.
+ * @returns VERR_FILE_NOT_LOCKED if region was not locked.
+ * @param   File        Handle to the file.
+ * @param   offLock     Offset of lock start.
+ * @param   cbLock      Length of region to unlock, may overlap the end of file.
+ */
+RTDECL(int)  RTFileUnlock(RTFILE File, int64_t offLock, uint64_t cbLock);
+
+/** @} */
+
+
+/**
+ * Query information about an open file.
+ *
+ * @returns iprt status code.
+ *
+ * @param   File                    Handle to the file.
+ * @param   pObjInfo                Object information structure to be filled on successful return.
+ * @param   enmAdditionalAttribs    Which set of additional attributes to request.
+ *                                  Use RTFSOBJATTRADD_NOTHING if this doesn't matter.
+ */
+RTDECL(int) RTFileQueryInfo(RTFILE File, PRTFSOBJINFO pObjInfo, RTFSOBJATTRADD enmAdditionalAttribs);
+
+/**
+ * Changes one or more of the timestamps associated of file system object.
+ *
+ * @returns iprt status code.
+ * @retval  VERR_NOT_SUPPORTED is returned if the operation isn't supported by
+ *          the OS.
+ *
+ * @param   File                Handle to the file.
+ * @param   pAccessTime         Pointer to the new access time. NULL if not to be changed.
+ * @param   pModificationTime   Pointer to the new modifcation time. NULL if not to be changed.
+ * @param   pChangeTime         Pointer to the new change time. NULL if not to be changed.
+ * @param   pBirthTime          Pointer to the new time of birth. NULL if not to be changed.
+ *
+ * @remark  The file system might not implement all these time attributes,
+ *          the API will ignore the ones which aren't supported.
+ *
+ * @remark  The file system might not implement the time resolution
+ *          employed by this interface, the time will be chopped to fit.
+ *
+ * @remark  The file system may update the change time even if it's
+ *          not specified.
+ *
+ * @remark  POSIX can only set Access & Modification and will always set both.
+ */
+RTDECL(int) RTFileSetTimes(RTFILE File, PCRTTIMESPEC pAccessTime, PCRTTIMESPEC pModificationTime,
+                           PCRTTIMESPEC pChangeTime, PCRTTIMESPEC pBirthTime);
+
+/**
+ * Gets one or more of the timestamps associated of file system object.
+ *
+ * @returns iprt status code.
+ * @param   File                Handle to the file.
+ * @param   pAccessTime         Where to store the access time. NULL is ok.
+ * @param   pModificationTime   Where to store the modifcation time. NULL is ok.
+ * @param   pChangeTime         Where to store the change time. NULL is ok.
+ * @param   pBirthTime          Where to store the time of birth. NULL is ok.
+ *
+ * @remark  This is wrapper around RTFileQueryInfo() and exists to complement RTFileSetTimes().
+ */
+RTDECL(int) RTFileGetTimes(RTFILE File, PRTTIMESPEC pAccessTime, PRTTIMESPEC pModificationTime,
+                           PRTTIMESPEC pChangeTime, PRTTIMESPEC pBirthTime);
+
+/**
+ * Changes the mode flags of an open file.
+ *
+ * The API requires at least one of the mode flag sets (Unix/Dos) to
+ * be set. The type is ignored.
+ *
+ * @returns iprt status code.
+ * @param   File        Handle to the file.
+ * @param   fMode       The new file mode, see @ref grp_rt_fs for details.
+ */
+RTDECL(int) RTFileSetMode(RTFILE File, RTFMODE fMode);
+
+/**
+ * Gets the mode flags of an open file.
+ *
+ * @returns iprt status code.
+ * @param   File        Handle to the file.
+ * @param   pfMode      Where to store the file mode, see @ref grp_rt_fs for details.
+ *
+ * @remark  This is wrapper around RTFileQueryInfo()
+ *          and exists to complement RTFileSetMode().
+ */
+RTDECL(int) RTFileGetMode(RTFILE File, uint32_t *pfMode);
+
+/**
+ * Changes the owner and/or group of an open file.
+ *
+ * @returns iprt status code.
+ * @param   File        Handle to the file.
+ * @param   uid         The new file owner user id.  Pass NIL_RTUID to leave
+ *                      this unchanged.
+ * @param   gid         The new group id.  Pass NIL_RTGID to leave this
+ *                      unchanged.
+ */
+RTDECL(int) RTFileSetOwner(RTFILE File, uint32_t uid, uint32_t gid);
+
+/**
+ * Gets the owner and/or group of an open file.
+ *
+ * @returns iprt status code.
+ * @param   File        Handle to the file.
+ * @param   pUid        Where to store the owner user id. NULL is ok.
+ * @param   pGid        Where to store the group id. NULL is ok.
+ *
+ * @remark  This is wrapper around RTFileQueryInfo() and exists to complement RTFileGetOwner().
+ */
+RTDECL(int) RTFileGetOwner(RTFILE File, uint32_t *pUid, uint32_t *pGid);
+
+/**
+ * Executes an IOCTL on a file descriptor.
+ *
+ * This function is currently only available in L4 and posix environments.
+ * Attemps at calling it from code shared with any other platforms will break things!
+ *
+ * The rational for defining this API is to simplify L4 porting of audio drivers,
+ * and to remove some of the assumptions on RTFILE being a file descriptor on
+ * platforms using the posix file implementation.
+ *
+ * @returns iprt status code.
+ * @param   File        Handle to the file.
+ * @param   ulRequest   IOCTL request to carry out.
+ * @param   pvData      IOCTL data.
+ * @param   cbData      Size of the IOCTL data.
+ * @param   piRet       Return value of the IOCTL request.
+ */
+RTDECL(int) RTFileIoCtl(RTFILE File, unsigned long ulRequest, void *pvData, unsigned cbData, int *piRet);
+
+/**
+ * Query the sizes of a filesystem.
+ *
+ * @returns iprt status code.
+ * @retval  VERR_NOT_SUPPORTED is returned if the operation isn't supported by
+ *          the OS.
+ *
+ * @param   hFile       The file handle.
+ * @param   pcbTotal    Where to store the total filesystem space. (Optional)
+ * @param   pcbFree     Where to store the remaining free space in the filesystem. (Optional)
+ * @param   pcbBlock    Where to store the block size. (Optional)
+ * @param   pcbSector   Where to store the sector size. (Optional)
+ *
+ * @sa      RTFsQuerySizes
+ */
+RTDECL(int) RTFileQueryFsSizes(RTFILE hFile, PRTFOFF pcbTotal, RTFOFF *pcbFree,
+                               uint32_t *pcbBlock, uint32_t *pcbSector);
+
+/**
+ * Reads the file into memory.
+ *
+ * The caller must free the memory using RTFileReadAllFree().
+ *
+ * @returns IPRT status code.
+ * @param   pszFilename     The name of the file.
+ * @param   ppvFile         Where to store the pointer to the memory on successful return.
+ * @param   pcbFile         Where to store the size of the returned memory.
+ *
+ * @remarks Note that this function may be implemented using memory mapping, which means
+ *          that the file may remain open until RTFileReadAllFree() is called. It also
+ *          means that the return memory may reflect the state of the file when it's
+ *          accessed instead of when this call was done. So, in short, don't use this
+ *          API for volatile files, then rather use the extended variant with a
+ *          yet-to-be-defined flag.
+ */
+RTDECL(int) RTFileReadAll(const char *pszFilename, void **ppvFile, size_t *pcbFile);
+
+/**
+ * Reads the file into memory.
+ *
+ * The caller must free the memory using RTFileReadAllFree().
+ *
+ * @returns IPRT status code.
+ * @param   pszFilename     The name of the file.
+ * @param   off             The offset to start reading at.
+ * @param   cbMax           The maximum number of bytes to read into memory. Specify RTFOFF_MAX
+ *                          to read to the end of the file.
+ * @param   fFlags          See RTFILE_RDALL_*.
+ * @param   ppvFile         Where to store the pointer to the memory on successful return.
+ * @param   pcbFile         Where to store the size of the returned memory.
+ *
+ * @remarks See the remarks for RTFileReadAll.
+ */
+RTDECL(int) RTFileReadAllEx(const char *pszFilename, RTFOFF off, RTFOFF cbMax, uint32_t fFlags, void **ppvFile, size_t *pcbFile);
+
+/**
+ * Reads the file into memory.
+ *
+ * The caller must free the memory using RTFileReadAllFree().
+ *
+ * @returns IPRT status code.
+ * @param   File            The handle to the file.
+ * @param   ppvFile         Where to store the pointer to the memory on successful return.
+ * @param   pcbFile         Where to store the size of the returned memory.
+ *
+ * @remarks See the remarks for RTFileReadAll.
+ */
+RTDECL(int) RTFileReadAllByHandle(RTFILE File, void **ppvFile, size_t *pcbFile);
+
+/**
+ * Reads the file into memory.
+ *
+ * The caller must free the memory using RTFileReadAllFree().
+ *
+ * @returns IPRT status code.
+ * @param   File            The handle to the file.
+ * @param   off             The offset to start reading at.
+ * @param   cbMax           The maximum number of bytes to read into memory. Specify RTFOFF_MAX
+ *                          to read to the end of the file.
+ * @param   fFlags          See RTFILE_RDALL_*.
+ * @param   ppvFile         Where to store the pointer to the memory on successful return.
+ * @param   pcbFile         Where to store the size of the returned memory.
+ *
+ * @remarks See the remarks for RTFileReadAll.
+ */
+RTDECL(int) RTFileReadAllByHandleEx(RTFILE File, RTFOFF off, RTFOFF cbMax, uint32_t fFlags, void **ppvFile, size_t *pcbFile);
+
+/**
+ * Frees the memory returned by one of the RTFileReadAll(), RTFileReadAllEx(),
+ * RTFileReadAllByHandle() and RTFileReadAllByHandleEx() functions.
+ *
+ * @param   pvFile          Pointer to the memory.
+ * @param   cbFile          The size of the memory.
+ */
+RTDECL(void) RTFileReadAllFree(void *pvFile, size_t cbFile);
+
+/** @name RTFileReadAllEx and RTFileReadAllHandleEx flags
+ * The open flags are ignored by RTFileReadAllHandleEx.
+ * @{ */
+#define RTFILE_RDALL_O_DENY_NONE            RTFILE_O_DENY_NONE
+#define RTFILE_RDALL_O_DENY_READ            RTFILE_O_DENY_READ
+#define RTFILE_RDALL_O_DENY_WRITE           RTFILE_O_DENY_WRITE
+#define RTFILE_RDALL_O_DENY_READWRITE       RTFILE_O_DENY_READWRITE
+#define RTFILE_RDALL_O_DENY_ALL             RTFILE_O_DENY_ALL
+#define RTFILE_RDALL_O_DENY_NOT_DELETE      RTFILE_O_DENY_NOT_DELETE
+#define RTFILE_RDALL_O_DENY_MASK            RTFILE_O_DENY_MASK
+/** Fail with VERR_OUT_OF_RANGE if the file size exceeds the specified maximum
+ * size.  The default behavior is to cap the size at cbMax. */
+#define RTFILE_RDALL_F_FAIL_ON_MAX_SIZE     RT_BIT_32(30)
+/** Add a trailing zero byte to facilitate reading text files. */
+#define RTFILE_RDALL_F_TRAILING_ZERO_BYTE   RT_BIT_32(31)
+/** Mask of valid flags. */
+#define RTFILE_RDALL_VALID_MASK             (RTFILE_RDALL_O_DENY_MASK | UINT32_C(0xc0000000))
+/** @} */
+
+/**
+ * Sets the current size of the file ensuring that all required blocks
+ * are allocated on the underlying medium.
+ *
+ * @returns IPRT status code.
+ * @retval  VERR_NOT_SUPPORTED if either this operation is not supported on the
+ *          current host in an efficient manner or the given combination of
+ *          flags is not supported.
+ * @param   hFile           The handle to the file.
+ * @param   cbSize          The new size of the file to allocate.
+ * @param   fFlags          Combination of RTFILE_ALLOC_SIZE_F_*
+ */
+RTDECL(int) RTFileSetAllocationSize(RTFILE hFile, uint64_t cbSize, uint32_t fFlags);
+
+/** @name RTFILE_ALLOC_SIZE_F_XXX - RTFileSetAllocationSize flags
+ * @{ */
+/** Default flags. */
+#define RTFILE_ALLOC_SIZE_F_DEFAULT         0
+/** Do not change the size of the file if the given size is bigger than the
+ * current file size.
+ *
+ * Useful to preallocate blocks beyond the current size for appending data in an
+ * efficient manner. Might not be supported on all hosts and will return
+ * VERR_NOT_SUPPORTED in that case. */
+#define RTFILE_ALLOC_SIZE_F_KEEP_SIZE       RT_BIT(0)
+/** Mask of valid flags. */
+#define RTFILE_ALLOC_SIZE_F_VALID           (RTFILE_ALLOC_SIZE_F_KEEP_SIZE)
+/** @} */
+
+
+#ifdef IN_RING3
+
+/** @defgroup grp_rt_fileio_async   RT File Async I/O API
+ *
+ * File operations are usually blocking the calling thread until they completed
+ * making it impossible to let the thread do anything else in-between. The RT
+ * File async I/O API provides an easy and efficient way to access files
+ * asynchronously using the native facilities provided by each operating system.
+ *
+ * @section sec_rt_asyncio_objects       Objects
+ *
+ * There are two objects used in this API.
+ *
+ * The first object is the request. A request contains every information needed
+ * two complete the file operation successfully like the start offset and
+ * pointer to the source or destination buffer. Requests are created with
+ * RTFileAioReqCreate() and destroyed with RTFileAioReqDestroy(). Because
+ * creating a request may require allocating various operating system dependent
+ * resources and may be quite expensive it is possible to use a request more
+ * than once to save CPU cycles. A request is constructed with either
+ * RTFileAioReqPrepareRead() which will set up a request to read from the given
+ * file or RTFileAioReqPrepareWrite() which will write to a given file.
+ *
+ * The second object is the context. A file is associated with a context and
+ * requests for this file may complete only on the context the file was
+ * associated with and not on the context given in RTFileAioCtxSubmit() (see
+ * below for further information). RTFileAioCtxWait() is used to wait for
+ * completion of requests which were associated with the context. While waiting
+ * for requests the thread can not respond to global state changes. That's why
+ * the API provides a way to let RTFileAioCtxWait() return immediately no matter
+ * how many requests have finished through RTFileAioCtxWakeup(). The return code
+ * is VERR_INTERRUPTED to let the thread know that he got interrupted.
+ *
+ * @section sec_rt_asyncio_request_states  Request states
+ *
+ * @b Created:
+ * After a request was created with RTFileAioReqCreate() it is in the same state
+ * like it just completed successfully. RTFileAioReqGetRC() will return
+ * VINF_SUCCESS and a transfer size of 0. RTFileAioReqGetUser() will return
+ * NULL. The request can be destroyed RTFileAioReqDestroy(). It is also allowed
+ * to prepare a the request for a data transfer with the RTFileAioReqPrepare*
+ * methods. Calling any other method like RTFileAioCtxSubmit() will return
+ * VERR_FILE_AIO_NOT_PREPARED and RTFileAioReqCancel() returns
+ * VERR_FILE_AIO_NOT_SUBMITTED.
+ *
+ * @b Prepared:
+ * A request will enter this state if one of the RTFileAioReqPrepare* methods is
+ * called. In this state you can still destroy and retrieve the user data
+ * associated with the request but trying to cancel the request or getting the
+ * result of the operation will return VERR_FILE_AIO_NOT_SUBMITTED.
+ *
+ * @b Submitted:
+ * A prepared request can be submitted with RTFileAioCtxSubmit(). If the
+ * operation succeeds it is not allowed to touch the request or free any
+ * resources until it completed through RTFileAioCtxWait(). The only allowed
+ * method is RTFileAioReqCancel() which tries to cancel the request. The request
+ * will go into the completed state and RTFileAioReqGetRC() will return
+ * VERR_FILE_AIO_CANCELED. If the request completes not matter if successfully
+ * or with an error it will switch into the completed state. RTFileReqDestroy()
+ * fails if the given request is in this state.
+ *
+ * @b Completed:
+ * The request will be in this state after it completed and returned through
+ * RTFileAioCtxWait(). RTFileAioReqGetRC() returns the final result code and the
+ * number of bytes transferred. The request can be used for new data transfers.
+ *
+ * @section sec_rt_asyncio_threading       Threading
+ *
+ * The API is a thin wrapper around the specific host OS APIs and therefore
+ * relies on the thread safety of the underlying API. The interesting functions
+ * with regards to thread safety are RTFileAioCtxSubmit() and
+ * RTFileAioCtxWait(). RTFileAioCtxWait() must not be called from different
+ * threads at the same time with the same context handle. The same applies to
+ * RTFileAioCtxSubmit(). However it is possible to submit new requests from a
+ * different thread while waiting for completed requests on another thread with
+ * RTFileAioCtxWait().
+ *
+ * @section sec_rt_asyncio_implementations  Differences in implementation
+ *
+ * Because the host APIs are quite different on every OS and every API has other
+ * limitations there are some things to consider to make the code as portable as
+ * possible.
+ *
+ * The first restriction at the moment is that every buffer has to be aligned to
+ * a 512 byte boundary. This limitation comes from the Linux io_* interface. To
+ * use the interface the file must be opened with O_DIRECT. This flag disables
+ * the kernel cache too which may degrade performance but is unfortunately the
+ * only way to make asynchronous I/O work till today (if O_DIRECT is omitted
+ * io_submit will revert to sychronous behavior and will return when the
+ * requests finished and when they are queued). It is mostly used by DBMS which
+ * do theire own caching. Furthermore there is no filesystem independent way to
+ * discover the restrictions at least for the 2.4 kernel series. Since 2.6 the
+ * 512 byte boundary seems to be used by all file systems. So Linus comment
+ * about this flag is comprehensible but Linux lacks an alternative at the
+ * moment.
+ *
+ * The next limitation applies only to Windows. Requests are not associated with
+ * the I/O context they are associated with but with the file the request is
+ * for. The file needs to be associated with exactly one I/O completion port and
+ * requests for this file will only arrive at that context after they completed
+ * and not on the context the request was submitted. To associate a file with a
+ * specific context RTFileAioCtxAssociateWithFile() is used. It is only
+ * implemented on Windows and does nothing on the other platforms. If the file
+ * needs to be associated with different context for some reason the file must
+ * be closed first. After it was opened again the new context can be associated
+ * with the other context. This can't be done by the API because there is no way
+ * to retrieve the flags the file was opened with.
+ *
+ * @{
+ */
+
+/**
+ * Global limits for the AIO API.
+ */
+typedef struct RTFILEAIOLIMITS
+{
+    /** Global number of simultaneous outstanding requests allowed.
+     *  RTFILEAIO_UNLIMITED_REQS means no limit. */
+    uint32_t cReqsOutstandingMax;
+    /** The alignment data buffers need to have.
+     * 0 means no alignment restrictions. */
+    uint32_t cbBufferAlignment;
+} RTFILEAIOLIMITS;
+/** A pointer to a AIO limits structure. */
+typedef RTFILEAIOLIMITS *PRTFILEAIOLIMITS;
+
+/**
+ * Returns the global limits for the AIO API.
+ *
+ * @returns IPRT status code.
+ * @retval  VERR_NOT_SUPPORTED if the host does not support the async I/O API.
+ *
+ * @param   pAioLimits      Where to store the global limit information.
+ */
+RTDECL(int) RTFileAioGetLimits(PRTFILEAIOLIMITS pAioLimits);
+
+/**
+ * Creates an async I/O request handle.
+ *
+ * @returns IPRT status code.
+ * @param   phReq           Where to store the request handle.
+ */
+RTDECL(int) RTFileAioReqCreate(PRTFILEAIOREQ phReq);
+
+/**
+ * Destroys an async I/O request handle.
+ *
+ * @returns IPRT status code.
+ * @retval  VERR_FILE_AIO_IN_PROGRESS if the request is still in progress.
+ *
+ * @param   hReq            The request handle.
+ */
+RTDECL(int) RTFileAioReqDestroy(RTFILEAIOREQ hReq);
+
+/**
+ * Prepares an async read request.
+ *
+ * @returns IPRT status code.
+ * @retval  VERR_FILE_AIO_IN_PROGRESS if the request is still in progress.
+ *
+ * @param   hReq            The request handle.
+ * @param   hFile           The file to read from.
+ * @param   off             The offset to start reading at.
+ * @param   pvBuf           Where to store the read bits.
+ * @param   cbRead          Number of bytes to read.
+ * @param   pvUser          Opaque user data associated with this request which
+ *                          can be retrieved with RTFileAioReqGetUser().
+ */
+RTDECL(int) RTFileAioReqPrepareRead(RTFILEAIOREQ hReq, RTFILE hFile, RTFOFF off,
+                                    void *pvBuf, size_t cbRead, void *pvUser);
+
+/**
+ * Prepares an async write request.
+ *
+ * @returns IPRT status code.
+ * @retval  VERR_FILE_AIO_IN_PROGRESS if the request is still in progress.
+ *
+ * @param   hReq            The request handle.
+ * @param   hFile           The file to write to.
+ * @param   off             The offset to start writing at.
+ * @param   pvBuf           The bits to write.
+ * @param   cbWrite         Number of bytes to write.
+ * @param   pvUser          Opaque user data associated with this request which
+ *                          can be retrieved with RTFileAioReqGetUser().
+ */
+RTDECL(int) RTFileAioReqPrepareWrite(RTFILEAIOREQ hReq, RTFILE hFile, RTFOFF off,
+                                     void const *pvBuf, size_t cbWrite, void *pvUser);
+
+/**
+ * Prepares an async flush of all cached data associated with a file handle.
+ *
+ * @returns IPRT status code.
+ * @retval  VERR_FILE_AIO_IN_PROGRESS if the request is still in progress.
+ *
+ * @param   hReq            The request handle.
+ * @param   hFile           The file to flush.
+ * @param   pvUser          Opaque user data associated with this request which
+ *                          can be retrieved with RTFileAioReqGetUser().
+ *
+ * @remarks May also flush other caches on some platforms.
+ */
+RTDECL(int) RTFileAioReqPrepareFlush(RTFILEAIOREQ hReq, RTFILE hFile, void *pvUser);
+
+/**
+ * Gets the opaque user data associated with the given request.
+ *
+ * @returns Opaque user data.
+ * @retval  NULL if the request hasn't been prepared yet.
+ *
+ * @param   hReq            The request handle.
+ */
+RTDECL(void *) RTFileAioReqGetUser(RTFILEAIOREQ hReq);
+
+/**
+ * Cancels a pending request.
+ *
+ * @returns IPRT status code.
+ * @retval  VINF_SUCCESS              If the request was canceled.
+ * @retval  VERR_FILE_AIO_NOT_SUBMITTED If the request wasn't submitted yet.
+ * @retval  VERR_FILE_AIO_IN_PROGRESS If the request could not be canceled because it is already processed.
+ * @retval  VERR_FILE_AIO_COMPLETED   If the request could not be canceled because it already completed.
+ *
+ * @param   hReq            The request to cancel.
+ */
+RTDECL(int) RTFileAioReqCancel(RTFILEAIOREQ hReq);
+
+/**
+ * Gets the status of a completed request.
+ *
+ * @returns The IPRT status code of the given request.
+ * @retval  VERR_FILE_AIO_NOT_SUBMITTED if the request wasn't submitted yet.
+ * @retval  VERR_FILE_AIO_CANCELED if the request was canceled.
+ * @retval  VERR_FILE_AIO_IN_PROGRESS if the request isn't yet completed.
+ *
+ * @param   hReq            The request handle.
+ * @param   pcbTransferred  Where to store the number of bytes transferred.
+ *                          Optional since it is not relevant for all kinds of
+ *                          requests.
+ */
+RTDECL(int) RTFileAioReqGetRC(RTFILEAIOREQ hReq, size_t *pcbTransferred);
+
+
+
+/**
+ * Creates an async I/O context.
+ *
+ * @todo briefly explain what an async context is here or in the page
+ *       above.
+ *
+ * @returns IPRT status code.
+ * @param   phAioCtx        Where to store the async I/O context handle.
+ * @param   cAioReqsMax     How many async I/O requests the context should be capable
+ *                          to handle. Pass RTFILEAIO_UNLIMITED_REQS if the
+ *                          context should support an unlimited number of
+ *                          requests.
+ * @param   fFlags          Combination of RTFILEAIOCTX_FLAGS_*.
+ */
+RTDECL(int) RTFileAioCtxCreate(PRTFILEAIOCTX phAioCtx, uint32_t cAioReqsMax,
+                               uint32_t fFlags);
+
+/** Unlimited number of requests.
+ * Used with RTFileAioCtxCreate and RTFileAioCtxGetMaxReqCount. */
+#define RTFILEAIO_UNLIMITED_REQS    UINT32_MAX
+
+/** When set RTFileAioCtxWait() will always wait for completing requests,
+ * even when there is none waiting currently, instead of returning
+ * VERR_FILE_AIO_NO_REQUEST. */
+#define RTFILEAIOCTX_FLAGS_WAIT_WITHOUT_PENDING_REQUESTS RT_BIT_32(0)
+/** mask of valid flags. */
+#define RTFILEAIOCTX_FLAGS_VALID_MASK (RTFILEAIOCTX_FLAGS_WAIT_WITHOUT_PENDING_REQUESTS)
+
+/**
+ * Destroys an async I/O context.
+ *
+ * @returns IPRT status code.
+ * @param   hAioCtx         The async I/O context handle.
+ */
+RTDECL(int) RTFileAioCtxDestroy(RTFILEAIOCTX hAioCtx);
+
+/**
+ * Get the maximum number of requests one aio context can handle.
+ *
+ * @returns Maximum number of tasks the context can handle.
+ *          RTFILEAIO_UNLIMITED_REQS if there is no limit.
+ *
+ * @param   hAioCtx         The async I/O context handle.
+ *                          If NIL_RTAIOCONTEXT is passed the maximum value
+ *                          which can be passed to RTFileAioCtxCreate()
+ *                          is returned.
+ */
+RTDECL(uint32_t) RTFileAioCtxGetMaxReqCount(RTFILEAIOCTX hAioCtx);
+
+/**
+ * Associates a file with an async I/O context.
+ * Requests for this file will arrive at the completion port
+ * associated with the file.
+ *
+ * @returns IPRT status code.
+ *
+ * @param   hAioCtx        The async I/O context handle.
+ * @param   hFile          The file handle.
+ */
+RTDECL(int) RTFileAioCtxAssociateWithFile(RTFILEAIOCTX hAioCtx, RTFILE hFile);
+
+/**
+ * Submits a set of requests to an async I/O context for processing.
+ *
+ * @returns IPRT status code.
+ * @returns VERR_FILE_AIO_INSUFFICIENT_RESSOURCES if the maximum number of
+ *          simultaneous outstanding requests would be exceeded.
+ *
+ * @param   hAioCtx         The async I/O context handle.
+ * @param   pahReqs         Pointer to an array of request handles.
+ * @param   cReqs           The number of entries in the array.
+ *
+ * @remarks It is possible that some requests could be submitted successfully
+ *          even if the method returns an error code. In that case RTFileAioReqGetRC()
+ *          can be used to determine the status of a request.
+ *          If it returns VERR_FILE_AIO_IN_PROGRESS it was submitted successfully.
+ *          Any other error code may indicate why the request failed.
+ *          VERR_FILE_AIO_NOT_SUBMITTED indicates that a request wasn't submitted
+ *          probably because the previous request encountered an error.
+ *
+ * @remarks @a cReqs uses the type size_t while it really is a uint32_t, this is
+ *          to avoid annoying warnings when using RT_ELEMENTS and similar
+ *          macros.
+ */
+RTDECL(int) RTFileAioCtxSubmit(RTFILEAIOCTX hAioCtx, PRTFILEAIOREQ pahReqs, size_t cReqs);
+
+/**
+ * Waits for request completion.
+ *
+ * Only one thread at a time may call this API on a context.
+ *
+ * @returns IPRT status code.
+ * @retval  VERR_INVALID_POINTER     If pcReqs or/and pahReqs are invalid.
+ * @retval  VERR_INVALID_HANDLE      If hAioCtx is invalid.
+ * @retval  VERR_OUT_OF_RANGE        If cMinReqs is larger than cReqs.
+ * @retval  VERR_INVALID_PARAMETER   If cReqs is 0.
+ * @retval  VERR_TIMEOUT             If cMinReqs didn't complete before the
+ *                                   timeout expired.
+ * @retval  VERR_INTERRUPTED         If the completion context was interrupted
+ *                                   by RTFileAioCtxWakeup().
+ * @retval  VERR_FILE_AIO_NO_REQUEST If there are no pending request.
+ *
+ * @param   hAioCtx         The async I/O context handle to wait and get
+ *                          completed requests from.
+ * @param   cMinReqs        The minimum number of requests which have to
+ *                          complete before this function returns.
+ * @param   cMillies        The number of milliseconds to wait before returning
+ *                          VERR_TIMEOUT.  Use RT_INDEFINITE_WAIT to wait
+ *                          forever.
+ * @param   pahReqs         Pointer to an array where the handles of the
+ *                          completed requests will be stored on success.
+ * @param   cReqs           The number of entries @a pahReqs can hold.
+ * @param   pcReqs          Where to store the number of returned (complete)
+ *                          requests. This will always be set.
+ *
+ * @remarks The wait will be resume if interrupted by a signal. An
+ *          RTFileAioCtxWaitNoResume variant can be added later if it becomes
+ *          necessary.
+ *
+ * @remarks @a cMinReqs and @a cReqs use the type size_t while they really are
+ *          uint32_t's, this is to avoid annoying warnings when using
+ *          RT_ELEMENTS and similar macros.
+ */
+RTDECL(int) RTFileAioCtxWait(RTFILEAIOCTX hAioCtx, size_t cMinReqs, RTMSINTERVAL cMillies,
+                             PRTFILEAIOREQ pahReqs, size_t cReqs, uint32_t *pcReqs);
+
+/**
+ * Forces any RTFileAioCtxWait() call on another thread to return immediately.
+ *
+ * @returns IPRT status code.
+ *
+ * @param   hAioCtx         The handle of the async I/O context to wakeup.
+ */
+RTDECL(int) RTFileAioCtxWakeup(RTFILEAIOCTX hAioCtx);
+
+/** @} */
+
+#endif /* IN_RING3 */
+
+/** @} */
+
+RT_C_DECLS_END
+
+#endif /* !IPRT_INCLUDED_file_h */
+