1TAR(1) General Commands Manual TAR(1)
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6 tar - tape archiver
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9 tar [ key ] [ name ... ]
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12 Tar saves and restores multiple files on a single file (usually a mag‐
13 netic tape, but it can be any file). Tar's actions are controlled by
14 the key argument. The key is a string of characters containing at most
15 one function letter and possibly one or more function modifiers. Other
16 arguments to tar are file or directory names specifying which files to
17 dump or restore. In all cases, appearance of a directory name refers
18 to the files and (recursively) subdirectories of that directory.
19 The function portion of the key is specified by one of the following
21 letters:
22 r The named files are written on the end of the tape. The c
24 function implies this.
25 x The named files are extracted from the tape. If the named file
27 matches a directory whose contents had been written onto the
28 tape, this directory is (recursively) extracted. The owner,
29 modification time, and mode are restored (if possible). If no
30 file argument is given, the entire content of the tape is
31 extracted. Note that if multiple entries specifying the same
32 file are on the tape, the last one overwrites all earlier.
33 t The names of the specified files are listed each time they
35 occur on the tape. If no file argument is given, all of the
36 names on the tape are listed.
37 u The named files are added to the tape if either they are not
39 already there or have been modified since last put on the tape.
40 c Create a new tape; writing begins on the beginning of the tape
42 instead of after the last file. This command implies r.
43 The following characters may be used in addition to the letter which
45 selects the function desired.
46 o On output, tar normally places information specifying owner
48 and modes of directories in the archive. Former versions of
49 tar, when encountering this information will give error mes‐
50 sage of the form
51 "<name>/: cannot create".
52 This modifier will suppress the directory information.
53 p This modifier says to restore files to their original modes,
55 ignoring the present umask(2). Setuid and sticky information
56 will also be restored to the super-user.
57 0, ..., 9 This modifier selects an alternate drive on which the tape is
59 mounted. The default is drive 0 at 1600 bpi, which is nor‐
60 mally /dev/rmt8.
61 v Normally tar does its work silently. The v (verbose) option
63 makes tar print the name of each file it treats preceded by
64 the function letter. With the t function, the verbose option
65 gives more information about the tape entries than just their
66 names.
67 w Tar prints the action to be taken followed by file name, then
69 wait for user confirmation. If a word beginning with `y' is
70 given, the action is done. Any other input means don't do it.
71 f Tar uses the next argument as the name of the archive instead
73 of /dev/rmt?. If the name of the file is `-', tar writes to
74 standard output or reads from standard input, whichever is
75 appropriate. Thus, tar can be used as the head or tail of a
76 filter chain. Tar can also be used to move hierarchies with
77 the command
78 cd fromdir; tar cf - . | (cd todir; tar xf -)
79 b Tar uses the next argument as the blocking factor for tape
81 records. The default is 20 (the maximum). This option should
82 only be used with raw magnetic tape archives (See f above).
83 The block size is determined automatically when reading tapes
84 (key letters `x' and `t').
85 l tells tar to complain if it cannot resolve all of the links
87 to the files dumped. If this is not specified, no error mes‐
88 sages are printed.
89 m tells tar not to restore the modification times. The modifi‐
91 cation time will be the time of extraction.
92 h Force tar to follow symbolic links as if they were normal
94 files or directories. Normally, tar does not follow symbolic
95 links.
96 B Forces input and output blocking to 20 blocks per record.
98 This option was added so that tar can work across a communi‐
99 cations channel where the blocking may not be maintained.
100 C If a file name is preceded by -C, then tar will perform a
102 chdir(2) to that file name. This allows multiple directories
103 not related by a close common parent to be archived using
104 short relative path names. For example, to archive files
105 from /usr/include and from /etc, one might use
106 tar c -C /usr include -C / etc
107 Previous restrictions dealing with tar's inability to properly handle
109 blocked archives have been lifted.
110
112 /dev/rmt?
113 /tmp/tar*
114
116 tar(5)
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119 Complaints about bad key characters and tape read/write errors.
120 Complaints if enough memory is not available to hold the link tables.
121
123 There is no way to ask for the n-th occurrence of a file.
124 Tape errors are handled ungracefully.
125 The u option can be slow.
126 The current limit on file name length is 100 characters.
127 There is no way selectively to follow symbolic links.
128 When extracting tapes created with the r or u options, directory modi‐
129 fication times may not be set correctly.
1307th Edition May 12, 1986 TAR(1)