Package: tar Version: 1.14-2 Severity: normal File: /bin/tar gnu tar's '--keep-newer-files' option does not work as expected:
There are cases where it deletes older files but does not extract the
corresponding archive members.
It does not preserve newer files, when followed by the '--overwrite' or
'--unlink-first' options.
This is a listing (line numbers prepended for easier reference) of
commands, which illustrates this. For explanations see below.
1 $ uname -srm
2 Linux 2.6.8-2-686 i686
3 $ tar --version
4 tar (GNU tar) 1.14
5 Copyright (C) 2004 Free Software Foundation, Inc.
6 This program comes with NO WARRANTY, to the extent permitted by law.
7 You may redistribute it under the terms of the GNU General Public License;
8 see the file named COPYING for details.
9 Written by John Gilmore and Jay Fenlason.
10 $ rm -rf -- archive 1 2
11 # Creating hierarchy 1/older/keep-newer-files
12 # Hardlinking hierarchy 1/older/keep-newer-files
13 # Creating hierarchy 1/older/keep-newer-files_overwrite
14 # Hardlinking hierarchy 1/older/keep-newer-files_overwrite
15 # Creating hierarchy 1/older/overwrite_keep-newer-files
16 # Hardlinking hierarchy 1/older/overwrite_keep-newer-files
17 # Creating hierarchy 1/older/keep-newer-files_unlink-first
18 # Hardlinking hierarchy 1/older/keep-newer-files_unlink-first
19 # Creating hierarchy 1/older/unlink-first_keep-newer-files
20 # Hardlinking hierarchy 1/older/unlink-first_keep-newer-files
21 $ sleep 3
22 # Creating hierarchy archive
23 $ tar -c -f archive.tar -- -C archive file
24 # table of contents of archive archive.tar:
25 $ tar -tv -f archive.tar
26 -rw------- helmut/helmut 5 2005-05-23 23:41:39 file
27 $ sleep 3
28 # Creating hierarchy 1/newer/keep-newer-files
29 # Hardlinking hierarchy 1/newer/keep-newer-files
30 # Creating hierarchy 1/newer/keep-newer-files_overwrite
31 # Hardlinking hierarchy 1/newer/keep-newer-files_overwrite
32 # Creating hierarchy 1/newer/overwrite_keep-newer-files
33 # Hardlinking hierarchy 1/newer/overwrite_keep-newer-files
34 # Creating hierarchy 1/newer/keep-newer-files_unlink-first
35 # Hardlinking hierarchy 1/newer/keep-newer-files_unlink-first
36 # Creating hierarchy 1/newer/unlink-first_keep-newer-files
37 # Hardlinking hierarchy 1/newer/unlink-first_keep-newer-files
38 $ sleep 3
39 $ ls -dogi -ctr -- \
40 1/older/keep-newer-files/file \
41 2/older/keep-newer-files/file \
42 1/older/keep-newer-files_overwrite/file \
43 2/older/keep-newer-files_overwrite/file \
44 1/older/overwrite_keep-newer-files/file \
45 2/older/overwrite_keep-newer-files/file \
46 1/older/keep-newer-files_unlink-first/file \
47 2/older/keep-newer-files_unlink-first/file \
48 1/older/unlink-first_keep-newer-files/file \
49 2/older/unlink-first_keep-newer-files/file \
50 archive/file \
51 1/newer/keep-newer-files/file \
52 2/newer/keep-newer-files/file \
53 1/newer/keep-newer-files_overwrite/file \
54 2/newer/keep-newer-files_overwrite/file \
55 1/newer/overwrite_keep-newer-files/file \
56 2/newer/overwrite_keep-newer-files/file \
57 1/newer/keep-newer-files_unlink-first/file \
58 2/newer/keep-newer-files_unlink-first/file \
59 1/newer/unlink-first_keep-newer-files/file \
60 2/newer/unlink-first_keep-newer-files/file
61 831408 -rw------- 2 0 2005-05-23 23:41:35+0200
2/older/keep-newer-files/file
62 831408 -rw------- 2 0 2005-05-23 23:41:35+0200
1/older/keep-newer-files/file
63 831413 -rw------- 2 1 2005-05-23 23:41:35+0200
2/older/keep-newer-files_overwrite/file
64 831413 -rw------- 2 1 2005-05-23 23:41:35+0200
1/older/keep-newer-files_overwrite/file
65 831416 -rw------- 2 2 2005-05-23 23:41:35+0200
2/older/overwrite_keep-newer-files/file
66 831416 -rw------- 2 2 2005-05-23 23:41:35+0200
1/older/overwrite_keep-newer-files/file
67 831419 -rw------- 2 3 2005-05-23 23:41:36+0200
2/older/keep-newer-files_unlink-first/file
68 831419 -rw------- 2 3 2005-05-23 23:41:36+0200
1/older/keep-newer-files_unlink-first/file
69 831422 -rw------- 2 4 2005-05-23 23:41:36+0200
2/older/unlink-first_keep-newer-files/file
70 831422 -rw------- 2 4 2005-05-23 23:41:36+0200
1/older/unlink-first_keep-newer-files/file
71 831425 -rw------- 1 5 2005-05-23 23:41:39+0200 archive/file
72 831429 -rw------- 2 6 2005-05-23 23:41:42+0200
2/newer/keep-newer-files/file
73 831429 -rw------- 2 6 2005-05-23 23:41:42+0200
1/newer/keep-newer-files/file
74 831433 -rw------- 2 7 2005-05-23 23:41:42+0200
2/newer/keep-newer-files_overwrite/file
75 831433 -rw------- 2 7 2005-05-23 23:41:42+0200
1/newer/keep-newer-files_overwrite/file
76 831436 -rw------- 2 8 2005-05-23 23:41:42+0200
2/newer/overwrite_keep-newer-files/file
77 831436 -rw------- 2 8 2005-05-23 23:41:42+0200
1/newer/overwrite_keep-newer-files/file
78 831439 -rw------- 2 9 2005-05-23 23:41:42+0200
2/newer/keep-newer-files_unlink-first/file
79 831439 -rw------- 2 9 2005-05-23 23:41:42+0200
1/newer/keep-newer-files_unlink-first/file
80 831442 -rw------- 2 10 2005-05-23 23:41:42+0200
2/newer/unlink-first_keep-newer-files/file
81 831442 -rw------- 2 10 2005-05-23 23:41:42+0200
1/newer/unlink-first_keep-newer-files/file
82 $ tar -x -f archive.tar --keep-newer-files \
83 -- -C 1/older/keep-newer-files
84 tar: file: Warning: Cannot stat: No such file or directory
85 tar: Current `file' is newer
86 $ ls -dogi -ctr -- 1/older/keep-newer-files/file
87 ls: 1/older/keep-newer-files/file: No such file or directory
88 $ tar -x -f archive.tar --keep-newer-files --overwrite \
89 -- -C 1/older/keep-newer-files_overwrite
90 $ ls -dogi -ctr -- 1/older/keep-newer-files_overwrite/file
91 831413 -rw------- 2 5 2005-05-23 23:41:45+0200
1/older/keep-newer-files_overwrite/file
92 $ tar -x -f archive.tar --overwrite --keep-newer-files \
93 -- -C 1/older/overwrite_keep-newer-files
94 tar: file: Warning: Cannot stat: No such file or directory
95 tar: Current `file' is newer
96 $ ls -dogi -ctr -- 1/older/overwrite_keep-newer-files/file
97 ls: 1/older/overwrite_keep-newer-files/file: No such file or directory
98 $ tar -x -f archive.tar --keep-newer-files --unlink-first \
99 -- -C 1/older/keep-newer-files_unlink-first
100 $ ls -dogi -ctr -- 1/older/keep-newer-files_unlink-first/file
101 831444 -rw------- 1 5 2005-05-23 23:41:45+0200
1/older/keep-newer-files_unlink-first/file
102 $ tar -x -f archive.tar --unlink-first --keep-newer-files \
103 -- -C 1/older/unlink-first_keep-newer-files
104 tar: file: Warning: Cannot stat: No such file or directory
105 tar: Current `file' is newer
106 $ ls -dogi -ctr -- 1/older/unlink-first_keep-newer-files/file
107 ls: 1/older/unlink-first_keep-newer-files/file: No such file or directory
108 $ tar -x -f archive.tar --keep-newer-files \
109 -- -C 1/newer/keep-newer-files
110 tar: Current `file' is newer
111 $ ls -dogi -ctr -- 1/newer/keep-newer-files/file
112 831429 -rw------- 2 6 2005-05-23 23:41:42+0200
1/newer/keep-newer-files/file
113 $ tar -x -f archive.tar --keep-newer-files --overwrite \
114 -- -C 1/newer/keep-newer-files_overwrite
115 $ ls -dogi -ctr -- 1/newer/keep-newer-files_overwrite/file
116 831433 -rw------- 2 5 2005-05-23 23:41:45+0200
1/newer/keep-newer-files_overwrite/file
117 $ tar -x -f archive.tar --overwrite --keep-newer-files \
118 -- -C 1/newer/overwrite_keep-newer-files
119 tar: Current `file' is newer
120 $ ls -dogi -ctr -- 1/newer/overwrite_keep-newer-files/file
121 831436 -rw------- 2 8 2005-05-23 23:41:42+0200
1/newer/overwrite_keep-newer-files/file
122 $ tar -x -f archive.tar --keep-newer-files --unlink-first \
123 -- -C 1/newer/keep-newer-files_unlink-first
124 $ ls -dogi -ctr -- 1/newer/keep-newer-files_unlink-first/file
125 831445 -rw------- 1 5 2005-05-23 23:41:45+0200
1/newer/keep-newer-files_unlink-first/file
126 $ tar -x -f archive.tar --unlink-first --keep-newer-files \
127 -- -C 1/newer/unlink-first_keep-newer-files
128 tar: Current `file' is newer
129 $ ls -dogi -ctr -- 1/newer/unlink-first_keep-newer-files/file
130 831442 -rw------- 2 10 2005-05-23 23:41:42+0200
1/newer/unlink-first_keep-newer-files/file
First (lines 11 to 20), five file hierarchies are built in the
subdirectory '1', each of them containing a file 'file' of unique length
(to be able to distinguish them when extracting). These hierarchies are
recursively hardlinked to corresponding hierarchies in subdirectory '2'
in order to distinguish whether tar overwrites or unlinks when
extracting.
After waiting 3 seconds, the 'archive' hierarchy is created the same way
(but not hardlinked) and stored in the 'archive.tar' file.
After waiting 3 seconds, five file hierarchies are built in
the same way and hardlinked as before (lines 28 to 37).
All created files can be seen at lines 61 to 81. The option "-c" is
supplied to the "ls" command to let it show the file status change time
rather than the data modification time (which could be reset by tar when
extracting archive members).
When extracting files, tar's option '--keep-newer-files' reveals some
errors:
First condition: The file in the file system is OLDER than the archive
member to be extracted from the archive.
So tar should extract it.
(1) As can be seen in lines 82 to 87, tar does not do that: It unlinks
the file but fails to extract the archive member, which is an ERROR.
(2) If '--keep-newer-files' is FOLLOWED by the additional option
'--overwrite', then the archive member is extracted (see lines 88 to
91). The file is not unlinked (its 2 hardlinks remain) but simply
overwritten, which is CORRECT.
(3) The same error like in (1) arises, when option '--keep-newer-files' is
PRECEDED by option '--overwrite' (see lines 92 to 97): The old file
is unlinked and no file is created.
(4) If '--keep-newer-files' is FOLLOWED by the additional option
'--unlink-first', then the archive member is extracted (see line 98
to 101). The file is unlinked (the hardlink is broken), which is
CORRECT.
(5) The same error like in (1) arises, when option '--keep-newer-files'
is PRECEDED by option '--unlink-first' (see lines 102 to 107): The
old file is unlinked and no file is created.
Second condition: The file in the file system is NEWER than the archive
member to be extracted from the archive.
So tar should not extract it.
(6) Tar does not extract the archive member (lines 108 to 112): The file
status change date, the link count, and the file size remain
unchanged (compare with line 73), which is CORRECT.
(7) If '--keep-newer-files' is FOLLOWED by '--overwrite', then the
archive member is extracted (see lines 113 to 116): The file is
overwritten rather than preserved. The link count remains 2, but the
file size and the file status change date is changed, which is an
ERROR.
(8) If '--keep-newer-files' is PRECEDED by option '--overwrite' (lines
117 to 121), the file is preserved like in (6), which is CORRECT.
(9) If '--keep-newer-files' is FOLLOWED by '--unlink-first', then the
archive member is extracted (lines 122 to 125): The file is unlinked
and created rather than preserved. The hardlink is broken, and the
file size and the file status change date is changed, which is an
ERROR.
(10) If '--keep-newer-files' is PRECEDED by option '--unlink-first (lines
126 to 130), the file is preserved like in (6), which is CORRECT.
-- System Information:
Debian Release: 3.1
APT prefers testing
APT policy: (500, 'testing')
Architecture: i386 (i686)
Kernel: Linux 2.6.8-2-686
Locale: LANG=C, LC_CTYPE=de_DE.UTF-8 (charmap=UTF-8)
Versions of packages tar depends on:
ii libc6 2.3.2.ds1-21 GNU C Library: Shared libraries an
-- no debconf information
This is the shell script, which produced the listing above (pipe it to
"pr -tTi -n' 3'" to get line numbers):
binq3mmSKfFGW.bin
Description: shell script to test gnu tar's '--keep-newer-files' option
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