2 XZ Utils User-Visible Changes
3 =============================
7 * xz --force now (de)compresses files that have setuid, setgid,
8 or sticky bit set and files that have multiple hard links.
9 The man page had it documented this way already, but the code
12 * gzip and bzip2 support in xzdiff was fixed.
16 * Minor fix to Czech translation
21 Only the most important changes compared to 4.999.9beta are listed
22 here. One change is especially important:
24 * The memory usage limit is now disabled by default. Some scripts
25 written before this change may have used --memory=max on xz command
26 line or in XZ_OPT. THESE USES OF --memory=max SHOULD BE REMOVED
27 NOW, because they interfere with user's ability to set the memory
28 usage limit himself. If user-specified limit causes problems to
29 your script, blame the user.
31 Other significant changes:
33 * Added support for XZ_DEFAULTS environment variable. This variable
34 allows users to set default options for xz, e.g. default memory
35 usage limit or default compression level. Scripts that use xz
36 must never set or unset XZ_DEFAULTS. Scripts should use XZ_OPT
37 instead if they need a way to pass options to xz via an
40 * The compression settings associated with the preset levels
41 -0 ... -9 have been changed. --extreme was changed a little too.
42 It is now less likely to make compression worse, but with some
43 files the new --extreme may compress slightly worse than the old
46 * If a preset level (-0 ... -9) is specified after a custom filter
47 chain options have been used (e.g. --lzma2), the custom filter
48 chain will be forgotten. Earlier the preset options were
49 completely ignored after custom filter chain options had been
52 * xz will create sparse files when decompressing if the uncompressed
53 data contains long sequences of binary zeros. This is done even
54 when writing to standard output that is connected to a regular
55 file and certain additional conditions are met to make it safe.
57 * Support for "xz --list" was added. Combine with --verbose or
58 --verbose --verbose (-vv) for detailed output.
60 * I had hoped that liblzma API would have been stable after
61 4.999.9beta, but there have been a couple of changes in the
62 advanced features, which don't affect most applications:
64 - Index handling code was revised. If you were using the old
65 API, you will get a compiler error (so it's easy to notice).
67 - A subtle but important change was made to the Block handling
68 API. lzma_block.version has to be initialized even for
69 lzma_block_header_decode(). Code that doesn't do it will work
70 for now, but might break in the future, which makes this API
73 * The major soname has been bumped to 5.0.0. liblzma API and ABI
74 are now stable, so the need to recompile programs linking against
75 liblzma shouldn't arise soon.