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diff --git a/contrib/tar/README b/contrib/tar/README new file mode 100644 index 0000000..5970df8 --- /dev/null +++ b/contrib/tar/README @@ -0,0 +1,196 @@ +README for GNU tar + + Copyright 1990, 1991, 1992, 1994, 1997, 1998, 1999, 2000, 2001 + Free Software Foundation, Inc. + + This file is part of GNU tar. + + GNU tar 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; either version 2, or (at your option) + any later version. + + GNU tar 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 tar; see the file COPYING. If not, write to + the Free Software Foundation, Inc., 59 Temple Place - Suite 330, + Boston, MA 02111-1307, USA. + + +Please glance through *all* sections of this +`README' file before starting configuration. Also make sure you read files +`ABOUT-NLS' and `INSTALL' if you are not familiar with them already. + +If you got the `tar' distribution in `shar' format, time stamps ought to be +properly restored; do not ignore such complaints at `unshar' time. + +GNU `tar' saves many files together into a single tape or disk +archive, and can restore individual files from the archive. It includes +multivolume support, the ability to archive sparse files, automatic archive +compression/decompression, remote archives and special features that allow +`tar' to be used for incremental and full backups. This distribution +also includes `rmt', the remote tape server. The `mt' tape drive control +program is in the GNU `cpio' distribution. + +GNU `tar' is derived from John Gilmore's public domain `tar'. + +See file `ABOUT-NLS' for how to customize this program to your language. +See file `COPYING' for copying conditions. +See file `INSTALL' for compilation and installation instructions. +See file `PORTS' for various ports of GNU tar to non-Unix systems. +See file `NEWS' for a list of major changes in the current release. +See file `THANKS' for a list of contributors. + +Besides those configure options documented in files `INSTALL' and +`ABOUT-NLS', an extra option may be accepted after `./configure': + +* `--disable-largefile' omits support for large files, even if the +operating system supports large files. Typically, large files are +those larger on 2 GB on a 32-bit host. + +The default archive device is now `stdin' on read and `stdout' on write. +The installer can still override this by presetting `DEFAULT_ARCHIVE' +in the environment before configuring (the behavior of `-[0-7]' or +`-[0-7]lmh' options in `tar' are then derived automatically). Similarly, +`DEFAULT_BLOCKING' can be preset to something else than 20. + +For comprehensive modifications to GNU tar, you might need tools beyond +those used in simple installations. Fully install GNU m4 1.4 first, +and only then, Autoconf 2.13 or later. Install Perl, then Automake +1.4 or later. You might need Bison 1.28 or later, and GNU tar itself. +All are available on GNU archive sites, like in +ftp://ftp.gnu.org/pub/gnu/. + +Send bug reports to `bug-tar@gnu.org'. (Beware, old-timers: it is +`@gnu', not `@prep'; and not `bug-gnu-utils' anymore.) A bug report is +an adequate description of the problem: your input, what you expected, +what you got, and why this is wrong. Diffs are welcome, but they only +describe a solution, from which the problem might be uneasy to infer. +If needed, submit actual data files with your report. Small data files +are preferred. Big files may sometimes be necessary, but do not send them +to the report address; rather take special arrangement with the maintainer. + +Your feedback will help us to make a better and more portable package. +Consider documentation errors as bugs, and report them as such. If you +develop anything pertaining to `tar' or have suggestions, let us know +and share your findings by writing to <bug-tar@gnu.org>. + + +Installation hints +------------------ + +Here are a few hints which might help installing `tar' on some systems. + +* gzip and bzip2. + +GNU tar uses the gzip and bzip2 programs to read and write compressed +archives. If you don't have these programs already, you need to +install them. Their sources can be found at: + +ftp://ftp.gnu.org/gnu/gzip/ +http://sourceware.cygnus.com/bzip2/ + +If you see the following symptoms: + + $ tar -xzf file.tar.gz + gzip: stdin: decompression OK, trailing garbage ignored + tar: Child returned status 2 + +then you have encountered a gzip incompatibility that should be fixed +in gzip test version 1.3, which as of this writing is available at +<ftp://alpha.gnu.org/gnu/gzip/>. You can work around the +incompatibility by using a shell command like + `gzip -d <file.tar.gz | tar -xzf -'. + +* Solaris issues. + +GNU tar exercises many features that can cause problems with older GCC +versions. In particular, GCC 2.8.1 (sparc, -O1 or -O2) is known to +miscompile GNU tar. No compiler-related problems have been reported +when using GCC 2.95.2 or later. + +Recent versions of Solaris tar sport a new -E option to generate +extended headers in an undocumented format. GNU tar does not +understand these headers. + +* Static linking. + +Some platform will, by default, prepare a smaller `tar' executable +which depends on shared libraries. Since GNU `tar' may be used for +system-level backups and disaster recovery, installers might prefer to +force static linking, making a bigger `tar' executable maybe, but able to +work standalone, in situations where shared libraries are not available. +The way to achieve static linking varies between systems. Set LDFLAGS +to a value from the table below, before configuration (see `INSTALL'). + + Platform Compiler LDFLAGS + + (any) Gnu C -static + AIX (vendor) -bnso -bI:/lib/syscalls.exp + HPUX (vendor) -Wl,-a,archive + IRIX (vendor) -non_shared + OSF (vendor) -non_shared + SCO 3.2v5 (vendor) -dn + Solaris (vendor) -Bstatic + SunOS (vendor) -Bstatic + +* Failed tests `ignfail.sh' or `incremen.sh'. + +In an NFS environment, lack of synchronization between machine clocks +might create difficulties to any tool comparing dates and file time stamps, +like `tar' in incremental dumps. This has been a recurrent problem with +GNU Make for the last few years. We would like a general solution. + +* BSD compatibility matters. + +Set LIBS to `-lbsd' before configuration (see `INSTALL') if the linker +complains about `bsd_ioctl' (Slackware). Also set CPPFLAGS to +`-I/usr/include/bsd' if <sgtty.h> is not found (Slackware). + +* OPENStep 4.2 swap files + +Tar cannot read the file /private/vm/swapfile.front (even as root). +This file is not a real file, but some kind of uncompressed view of +the real compressed swap file; there is no reason to back it up, so +the simplest workaround is to avoid tarring this file. + + +Special topics +-------------- + +Here are a few special matters about GNU `tar', not related to build +matters. See previous section for such. + +* File attributes. + +About *security*, it is probable that future releases of `tar' will have +some behavior changed. There are many pending suggestions to choose from. +Today, extracting an archive not being `root', `tar' will restore suid/sgid +bits on files but owned by the extracting user. `root' automatically gets +a lot of special privileges, `-p' might later become required to get them. + +GNU `tar' does not properly restore symlink attributes. Various systems +implement flavors of symbolic links showing different behavior and +properties. We did not successfully sorted all these out yet. Currently, +the `lchown' call will be used if available, but that's all. + +* POSIX compliance. + +GNU `tar' implements an early draft of the POSIX 1003.1 `ustar' standard +which is different from the final standard. This will be progressively +corrected over the incoming few years. Don't be mislead by the mere +existence of the --posix option. Later releases will become able to +read truly POSIX archives, and also to produce them under option. (Also, +if you look at the internals, don't take the GNU extensions you see for +granted, as they are planned to change.) GNU tar 2.0 will produce POSIX +archives by default, but there is a long way before we get there. + +* What's next? + +In the future we will try to release tar-1.14 as soon as possible and +start merging with paxutils afterwards. We'll also try to rewrite +some parts of the documentation after paxutils has been merged. |
