INTRODUCTION
-This is wimlib version 1.4.0 (May 2013). wimlib is a C library for creating,
-modifying, extracting, and mounting files in the Windows Imaging Format (WIM
-files). These files are normally created by using the `imagex.exe' utility on
-Windows, but wimlib is distributed with a free implementation of ImageX called
-"wimlib-imagex" for both UNIX and Windows.
+This is wimlib version 1.9.2-BETA (April 2016). wimlib is a C library for
+creating, modifying, extracting, and mounting files in the Windows Imaging
+Format (WIM files). wimlib and its command-line frontend 'wimlib-imagex'
+provide a free and cross-platform alternative to Microsoft's WIMGAPI, ImageX,
+and DISM.
INSTALLATION
-To install wimlib and wimlib-imagex on Windows you simply need to download and
-extract the ZIP file containing the latest binaries from the SourceForge page
-(http://sourceforge.net/projects/wimlib/), which you may have already done.
+To install wimlib and wimlib-imagex on UNIX-like systems, you can compile from
+source (e.g. './configure && make && sudo make install'). Alternatively, check
+if a package has already been prepared for your operating system. Example files
+for Debian and RPM packaging are in the debian/ and rpm/ directories.
-To install wimlib and wimlib-imagex on UNIX (with Linux being the primary
-supported and tested platform), you must compile it from the source code. At
-some point I might start posting RPMs and Debian packages for convenience.
+To install wimlib and wimlib-imagex on Windows, just download and extract the
+ZIP file containing the latest binaries. See README.WINDOWS for more details.
- WIM FILES
+All official wimlib releases are available from https://wimlib.net.
+
+ WIM FILES
A Windows Imaging (WIM) file is an archive designed primarily for archiving
Windows filesystems. However, it can be used on other platforms as well, with
some limitations. Like some other archive formats such as ZIP, files in WIM
-archives may be compressed. WIM files support two compression formats: LZX and
-XPRESS. Both are supported by wimlib.
+archives may be compressed. WIM archives support multiple compression formats,
+including LZX, XPRESS, and LZMS. All these formats are supported by wimlib.
+
+A WIM archive contains one or more "images", each of which is a logically
+independent directory tree. Each image has a 1-based index and usually a name.
+
+WIM archives provide data deduplication at the level of full file contents. In
+other words, each unique "file contents" is only stored once in the archive,
+regardless of how many files have that contents across all images.
-A WIM file consists of one or more "images". Each image is an independent
-top-level directory structure and is logically separate from all other images in
-the WIM. Each image has a name as well as a 1-based index in the WIM file. To
-save space, WIM archives automatically combine all duplicate files across all
-images.
+A WIM archive may be either stand-alone or split into multiple parts.
-A WIM file may be either stand-alone or split into multiple parts. Split WIMs
-are read-only and cannot be modified.
+An update of the WIM format --- first added by Microsoft for Windows 8 ---
+supports solid-mode compression. This refers to files being compressed together
+(e.g. as in a .tar.xz or .7z archive) rather than separately (e.g. as in a .zip
+archive). This usually produces a much better compression ratio. Solid
+archives are sometimes called "ESD files" by Microsoft and may have the ".esd"
+file extension rather than ".wim". They are supported in wimlib since v1.6.0.
IMAGEX IMPLEMENTATION
wimlib itself is a C library, and it provides a documented public API (See:
-http://wimlib.sourceforge.net) for other programs to use. However, it is also
+https://wimlib.net/apidoc) for other programs to use. However, it is also
distributed with a command-line program called "wimlib-imagex" that uses this
library to implement an imaging tool similar to Microsoft's ImageX.
wimlib-imagex supports almost all the capabilities of Microsoft's ImageX as well
-as additional capabilities. wimlib-imagex works on both UNIX and Windows,
-although some features differ between the platforms.
+as additional capabilities. wimlib-imagex works on both UNIX-like systems and
+Windows, although some features differ between the platforms.
Run `wimlib-imagex' with no arguments to see an overview of the available
commands and their syntax. For additional documentation:
- * If you have installed wimlib-imagex on UNIX, you will find further
- documentation in the man pages; run `man wimlib-imagex' to get started.
+ * If you have installed wimlib-imagex on a UNIX-like system, you will find
+ further documentation in the man pages; run `man wimlib-imagex' to get
+ started.
* If you have downloaded the Windows binary distribution, you will find the
documentation for wimlib-imagex in PDF format in the "doc" directory,
files are converted from UNIX-style "man pages", they do document
Windows-specific behavior when appropriate.
- COMPRESSION RATIO
-
-wimlib (and wimlib-imagex) can create XPRESS or LZX compressed WIM archives.
-Currently, the XPRESS compression ratio is slightly better than that provided by
-Microsoft's software, while the LZX compression ratio is approaching that of
-Microsoft's software but is not quite there yet. Running time is as good as or
-better than Microsoft's software, especially with multithreaded compression,
-available in wimlib v1.1.0 and later.
-
-The following tables compare the compression ratio and performance for creating
-a compressed Windows PE image (disk usage of about 524 MB, uncompressed WIM size
-361 MB):
-
- Table 1. WIM size
+ COMPRESSION
- XPRESS Compression LZX Compression
- wimlib-imagex (v1.2.1): 138,971,353 bytes 131,379,943 bytes
- Microsoft imagex.exe: 140,406,981 bytes 127,249,176 bytes
-
- Table 2. Time to create WIM
-
- XPRESS Compression LZX Compression
- wimlib-imagex (v1.2.1, 2 threads): 11 sec 17 sec
- Microsoft imagex.exe: 25 sec 89 sec
+wimlib (and wimlib-imagex) can create XPRESS, LZX, and LZMS compressed WIM
+archives. wimlib's compression codecs usually outperform and outcompress their
+closed-source Microsoft equivalents. Multiple compression levels and chunk
+sizes as well as solid mode compression are supported. Compression is
+multithreaded by default. Detailed benchmark results and descriptions of the
+algorithms used can be found at https://wimlib.net/compression.html.
NTFS SUPPORT
Windows-specific data are ordinarily ignored; however, there is also special
support for capturing and extracting images directly to/from unmounted NTFS
volumes. This was made possible with the help of libntfs-3g from the
- NTFS-3g project.
+ NTFS-3G project.
For both platforms the code for NTFS capture and extraction is complete enough
that it is possible to apply an image from the "install.wim" contained in recent
-Windows installation media (Vista, Windows 7, or Windows 8) directly to a NTFS
-filesystem, and then boot Windows from it after preparing the Boot Configuration
-Data. In addition, a Windows installation can be captured (or backed up) into a
-WIM file, and then re-applied later.
+Windows installation media (Vista or later) directly to an NTFS filesystem, and
+then boot Windows from it after preparing the Boot Configuration Data. In
+addition, a Windows installation can be captured (or backed up) into a WIM file,
+and then re-applied later.
WINDOWS PE
A major use for wimlib and wimlib-imagex is to create customized images of
-Windows PE, the Windows Preinstallation Environment, on either UNIX or Windows
-without having to rely on Microsoft's software and its restrictions and
-limitations.
+Windows PE, the Windows Preinstallation Environment, on either UNIX-like systems
+or Windows without having to rely on Microsoft's software and its restrictions
+and limitations.
Windows PE is a lightweight version of Windows that can run entirely from memory
and can be used to install Windows from local media or a network drive or
perform maintenance. It is the operating system that runs when you boot from
the Windows installation media.
-You can find Windows PE on the installation DVD for Windows Vista, Windows 7, or
-Windows 8, in the file `sources/boot.wim'. Windows PE can also be found in the
-Windows Automated Installation Kit (WAIK), which is free to download from
-Microsoft, inside the `WinPE.cab' file, which you can extract natively on
-Windows, or on UNIX if you install either the `cabextract' or `p7zip' programs.
+You can find Windows PE on the installation media for Windows (Vista or later)
+as the file `sources/boot.wim'. Windows PE can also be found in the Windows
+Automated Installation Kit (WAIK), which is free to download from Microsoft,
+inside the `WinPE.cab' file, which you can extract natively on Windows, or on
+UNIX-like systems if you install either the `cabextract' or `p7zip' programs.
In addition, Windows installations and recovery partitions frequently contain a
WIM containing an image of the Windows Recovery Environment, which is similar to
Windows PE.
-A shell script `mkwinpeimg' is distributed with wimlib on UNIX to ease the
-process of creating and customizing a bootable Windows PE image.
+A shell script `mkwinpeimg' is distributed with wimlib on UNIX-like systems to
+ease the process of creating and customizing a bootable Windows PE image.
DEPENDENCIES
This section documents the dependencies of wimlib and the programs distributed
-with it, when building for UNIX from source. If you have downloaded the Windows
-binary distribution of wimlib and wimlib-imagex then all dependencies were
-already included and this section is irrelevant.
+with it, when building for a UNIX-like system from source. If you have
+downloaded the Windows binary distribution of wimlib and wimlib-imagex then all
+dependencies were already included and this section is irrelevant.
* libxml2 (required)
- This is a commonly used free library to read and write XML files. You
- likely already have it installed as a dependency for some other program.
- For more information see http://xmlsoft.org/.
-
-* libfuse (optional but highly recommended)
- Unless configured with --without-fuse, wimlib requires a non-ancient
- version of libfuse to be installed. Most Linux distributions already
- include this, but make sure you have the libfuse package installed, and
- also libfuse-dev if your distribution distributes header files
- separately. FUSE also requires a kernel module. If the kernel module
- is available it will automatically be loaded if you try to mount a WIM
- file. For more information see http://fuse.sourceforge.net/. FUSE is
- also available for FreeBSD.
-
-* libntfs-3g (optional but highly recommended)
- Unless configured with --without-ntfs-3g, wimlib requires the library
- and headers for libntfs-3g version 2011-4-12 or later to be installed.
- Versions dated 2010-3-6 and earlier do not work because they are missing
- the header xattrs.h (and the file xattrs.c, which contains functions we
- need). libntfs-3g version 2013-1-13 is compatible only with wimlib
- 1.2.4 and later.
+ This is a commonly used free library to read and write XML documents.
+ Almost all Linux distributions should include this; however, you may
+ need to install the header files, which might be in a package named
+ "libxml2-dev" or similar. For more information see http://xmlsoft.org/.
+
+* libfuse (optional but recommended)
+ Unless configured --without-fuse, wimlib requires a non-ancient version
+ of libfuse. Most Linux distributions already include this, but make
+ sure you have the libfuse package installed, and also libfuse-dev if
+ your distribution distributes header files separately. FUSE also
+ requires a kernel module. If the kernel module is available it should
+ automatically be loaded if you try to mount a WIM image. For more
+ information see http://fuse.sourceforge.net/.
+
+* libattr (optional but recommended)
+ Unless configured --without-fuse, wimlib also requires libattr. Almost
+ all Linux distributions should include this; however, you may need to
+ install the header files, which might be in a package named "attr-dev",
+ "libattr1-dev", or similar.
+
+* libntfs-3g (optional but recommended)
+ Unless configured --without-ntfs-3g, wimlib requires the library and
+ headers for libntfs-3g version 2011-4-12 or later to be installed.
* OpenSSL / libcrypto (optional)
- wimlib can use the SHA1 message digest code from OpenSSL instead of
- compiling in yet another SHA1 implementation. (See LICENSE section.)
+ wimlib can use the SHA-1 message digest implementation from libcrypto
+ (usually provided by OpenSSL) instead of compiling in yet another SHA-1
+ implementation.
* cdrkit (optional)
* mtools (optional)
CONFIGURATION
This section documents the most important options that may be passed to the
-"configure" script when building the UNIX version from source:
+"configure" script when building from source:
--without-ntfs-3g
If libntfs-3g is not available or is not version 2011-4-12 or later,
wimlib can be built without it, in which case it will not be possible to
- apply or capture images directly to/from NTFS volumes.
+ capture or apply WIM images directly from/to NTFS volumes.
---without-fuse
- If libfuse or the FUSE kernel module is not available, wimlib can be
- compiled with --without-fuse. This will remove the ability to mount and
- unmount WIM files.
-
---without-libcrypto
- Build in functions for SHA1 rather than using external SHA1 functions
- from libcrypto (part of OpenSSL). The default is to use libcrypto if it
- is found on the system.
+ The default is --with-ntfs-3g when building for any UNIX-like system,
+ and --without-ntfs-3g when building for Windows.
---enable-xattr, --disable-xattr
- Enable or disable support for the extended-attributes interface to NTFS
- alternate data streams in mounted WIMs. To support these, wimlib
- requires that the setxattr() function and the attr/xattr.h header are
- available. The default is to autodetect whether support is possible.
-
---disable-multithreaded-compression
- By default, data will be compressed using multiple threads when writing
- a WIM, unless only 1 processor is detected. Specify this option to
- disable support for this.
+--without-fuse
+ The --without-fuse option disables support for mounting WIM images.
+ This removes dependencies on libfuse, librt, and libattr. The wimmount,
+ wimmountrw, and wimunmount commands will not work.
---enable-ssse3-sha1
- Use a very fast assembly language implementation of SHA1 from Intel.
- Only use this if the build target supports the SSSE3 instructions.
+ The default is --with-fuse when building for Linux, and --without-fuse
+ otherwise.
---disable-error-messages
- Save some space by removing all error messages from the library.
+--without-libcrypto
+ Build in functions for SHA-1 rather than using external SHA-1 functions
+ from libcrypto (usually provided by OpenSSL).
---disable-assertions
- Remove assertions included by default.
+ The default is to use libcrypto if it is found on your system.
PORTABILITY
-wimlib has primarily been tested on Linux and Windows (primarily Windows 7, but
-also Windows XP and Windows 8).
+wimlib works on both UNIX-like systems (Linux, Mac OS X, FreeBSD, etc.) and
+Windows (XP and later).
-wimlib may work on FreeBSD and Mac OS X. However, this is not well tested. If
-you do not have libntfs-3g 2011-4-12 or later available, you must configure
-wimlib with --without-ntfs-3g. On FreeBSD, before mounting a WIM you need to
-load the POSIX message queue module (run `kldload mqueuefs').
+As much code as possible is shared among all supported platforms, but there
+necessarily are some differences in what features are supported on each platform
+and how they are implemented. Most notable is that file tree scanning and
+extraction are implemented separately for Windows, UNIX, and UNIX (NTFS-3G
+mode), to ensure a fast and feature-rich implementation of each platform/mode.
-wimlib has not been tested on big-endian CPU architectures.
+wimlib is mainly used on x86 and x86_64 CPUs, but it should also work on a
+number of other GCC-supported 32-bit or 64-bit architectures. It has been
+tested on the ARM and MIPS architectures.
+
+Currently, gcc and clang are the only supported compilers. A few nonstandard
+extensions are used in the code.
REFERENCES
-The WIM file format is specified in a document that can be found in the
-Microsoft Download Center. There is a similar document that specifies the LZX
-compression format, and a document that specifies the XPRESS compression format.
-However, many parts of these formats are poorly documented, and some parts have
-no documentation whatsoever. Some particularly poorly documented parts of the
-formats have had comments added in various places in the library code. Please
-see the code and/or ask me if you have any questions about the WIM file format
-as it exists in reality and not as it exists in Microsoft's poorly written
-documentation.
-
-The code in ntfs-apply.c and ntfs-capture.c uses the NTFS-3g library, which is a
-library for reading and writing to NTFS filesystems (the filesystem used by
-recent versions of Windows). See
-http://www.tuxera.com/community/ntfs-3g-download/ for more information.
+The WIM file format is partially specified in a document that can be found in
+the Microsoft Download Center. However, this document really only provides an
+overview of the format and is not a formal specification. It also does not
+cover later extensions of the format, such as solid resources.
-lzx-decompress.c, the code to decompress WIM file resources that are compressed
-using LZX compression, was originally based on code from the cabextract project
-(http://www.cabextract.org.uk) but has been rewritten.
+With regards to the supported compression formats:
-lzx-compress.c, the code to compress WIM file resources using LZX compression,
-was originally based on code written by Matthew Russotto (www.russotto.net/chm/)
-but has been rewritten.
+- Microsoft has official documentation for XPRESS that is of reasonable quality.
+- Microsoft has official documentation for LZX, but in two different documents,
+ neither of which is completely applicable to its use in the WIM format, and
+ the first of which contains multiple errors.
+- There does not seem to be any official documentation for LZMS, so my comments
+ and code in src/lzms_decompress.c may in fact be the best documentation
+ available for this particular compression format.
-lz77.c, the code to find LZ77 matches (used for both XPRESS and LZX
-compression), is based on code from zlib but has been rewritten.
+The algorithms used by wimlib's compression and decompression codecs are
+inspired by a variety of sources, including open source projects and computer
+science papers.
+
+The code in ntfs-3g_apply.c and ntfs-3g_capture.c uses the NTFS-3G library,
+which is a library for reading and writing to NTFS filesystems (the filesystem
+used by recent versions of Windows). See
+http://www.tuxera.com/community/ntfs-3g-download/ for more information.
A limited number of other free programs can handle some parts of the WIM
file format:
* 7-zip is able to extract and create WIMs (as well as files in many
other archive formats). However, wimlib is designed specifically to handle
WIM files and provides features previously only available in Microsoft's
- imagex.exe, such as the ability to mount WIMs read-write as well as
- read-only, the ability to create LZX or XPRESS compressed WIMs, and the
- correct handling of security descriptors and hard links.
+ implementation, such as the ability to mount WIMs read-write as well as
+ read-only, the ability to create compressed WIMs, the correct handling of
+ security descriptors and hard links, support for LZMS compression, and
+ support for solid archives.
* ImagePyX (https://github.com/maxpat78/ImagePyX) is a Python program that
- provides similar capabilities to wimlib-imagex. One thing to note, though,
- is that it does not support compression and decompression by itself, but
- instead relies on external native code, such as the codecs from wimlib.
+ provides some capabilities of wimlib-imagex, with the help of external
+ compression codecs.
-A very early version of wimlib is being used to deploy Windows 7 from the
-Ultimate Deployment Appliance. For more information see
-http://www.ultimatedeployment.org/.
+If you are looking for an archive format that provides features similar to WIM
+but was designed primarily for UNIX, you may want to consider SquashFS
+(http://squashfs.sourceforge.net/). However, you may find that wimlib works
+surprisingly well on UNIX. It will store hard links and symbolic links, and it
+has optional support for storing UNIX owners, groups, modes, and special files
+such as device nodes and FIFOs. Actually, I use it to back up my own files on
+Linux!
-You can see the documentation about Microsoft's version of ImageX at
-http://technet.microsoft.com/en-us/library/cc749447(v=ws.10).aspx, so you can
-see how it compares to the version provided by this library.
+ HISTORY
-If you are looking for a UNIX archive format that provides features similar to
-WIM, I recommend you take a look at SquashFS (http://squashfs.sourceforge.net/).
+wimlib was originally a project started by Carl Thijssen for use on Linux in the
+Ultimate Deployment Appliance (http://www.ultimatedeployment.org/). Since then
+the code has been entirely rewritten and improved (main author: Eric Biggers).
+Windows support has been available since version 1.3.0 (March 2013). A list of
+version-to-version changes can be found in the NEWS file.
- LICENSE
+ LICENSE AND DISCLAIMER
-As of version 1.0.0, wimlib and all programs and scripts distributed with it are
-released under the GNU GPL version 3.0 or later.
+See COPYING for information about the license.
wimlib is independently developed and does not contain any code, data, or files
copyrighted by Microsoft. It is not known to be affected by any patents.
-On UNIX, if you do not want wimlib to be dynamically linked with libcrypto
-(OpenSSL), configure with --without-libcrypto. This replaces the SHA1
+On UNIX-like systems, if you do not want wimlib to be dynamically linked with
+libcrypto (OpenSSL), configure with --without-libcrypto. This replaces the SHA1
implementation with built-in code and there will be no difference in
functionality.
- DISCLAIMER
-
-wimlib comes with no warranty whatsoever. Use Microsoft's `imagex.exe' if you
-want to make sure your WIM files are made "correctly" (but beware: Microsoft's
-version contains some bugs).
-
-Please submit a bug report (to ebiggers3@gmail.com) if you find a bug in wimlib
-and/or wimlib-imagex.
-
-Be aware that some parts of the WIM file format are poorly documented or even
-completely undocumented, so I've just had to do the best I can to read and write
-WIMs that appear to be compatible with Microsoft's software.
+wimlib comes with no warranty whatsoever. Please submit a bug report (to
+ebiggers3@gmail.com) if you find a bug in wimlib and/or wimlib-imagex.
git://wimlib.net / wimlib / blobdiff