Gentoo Archives: gentoo-user

From: tastytea <gentoo@××××××××.de>
To: gentoo-user@l.g.o
Subject: Re: [gentoo-user] Re: [OT] tar exclude syntax tip
Date: Wed, 05 May 2021 14:24:05
Message-Id: 20210505162349.06cdc970@ventiloplattform.tastytea.de
In Reply to: [gentoo-user] Re: [OT] tar exclude syntax tip by nunojsilva@ist.utl.pt
1 On 2021-05-05 15:10+0100 <nunojsilva@×××××××.pt> (Nuno Silva) wrote:
2
3 > On 2021-05-05, tastytea wrote:
4 >
5 > > On 2021-05-05 09:33-0400 "Walter Dnes" <waltdnes@××××××××.org>
6 > > wrote:
7 > >> tar version
8 > >>
9 > >> ####################################################
10 > >> tar (GNU tar) 1.34
11 > >> Copyright (C) 2021 Free Software Foundation, Inc.
12 > >> License GPLv3+: GNU GPL version 3 or later
13 > >> <https://gnu.org/licenses/gpl.html>. This is free software: you are
14 > >> free to change and redistribute it. There is NO WARRANTY, to the
15 > >> extent permitted by law.
16 > >>
17 > >> Written by John Gilmore and Jay Fenlason.
18 > >> ####################################################
19 > >>
20 > >> I'm passing on this solution to help others avoid my frustration
21 > >> and wasted time. If you've done "RTFM" on tar, you'll find out
22 > >> that "TFM" is broken or out-of-date or whatever, re:
23 > >> "--exclude=PATTERN". I'm fighting the urge to turn this into a
24 > >> rant. Here's my situation...
25 > >>
26 > >> I either log in as root or "su -" and then "cd /home". I want to
27 > >> tar up /home/waltdnes, and transfer it to another machine. While
28 > >> I'm at it, I want to exlude directory /home/waltdnes/.cache/ and
29 > >> all *.xz files in directory /home/waltdnes/pm/ The "--exclude="
30 > >> never worked. After much hair pulling, I was ready to give up on
31 > >> the exclude, and simply transfer all the unnecessary garbage.
32 > >>
33 > >> Then "I asked Mr. Google". It seems that I wasn't the only
34 > >> person running into problems. After some searching, I finally
35 > >> found a syntax that works...
36 > >>
37 > >> ####################################################
38 > >> #!/bin/bash
39 > >> export GZIP=-9
40 > >> tar cvzf wd.tgz --exclude ".cache/*" --exclude "pm/*.xz" waltdnes
41 > >> ####################################################
42 > >>
43 > >> Notes...
44 > >>
45 > >> 1) This is obviously not in line with the man page. Specifically,
46 > >> "--exclude" is followed by one space, not an equals sign.
47 > >>
48 > >> 2) ***THERE MUST BE EXACTLY ONE SPACE BETWEEN EACH WORD***
49 > >>
50 > >> 3) All directories and/or files to exclude must be listed as
51 > >> relative paths to the directory being tarred, i.e. last parameter
52 > >> on the command line.
53 > >>
54 > >> 4) I don't know the maximum line-length, which would limit the
55 > >> number of --exclude entries. In those cases, I wonder if
56 > >> "--exclude-from=FILE" works as "--exclude-from FILE".
57 > >>
58 > >
59 > > This works fine here with “tar (GNU tar) 1.34”:
60 > >
61 > > $ mkdir -p a/b
62 > > $ touch a/file a/b/file
63 > > $ touch a/file.xz a/b/file.xz
64 > > $ tree a
65 > > a
66 > > ├── b
67 > > │   ├── file
68 > > │   └── file.xz
69 > > ├── file
70 > > └── file.xz
71 > >
72 > > 1 directory, 4 files
73 > > $ tar -cvzf test.tar.gz --exclude="a/file" --exclude="a/b/*.xz" a
74 > > a/
75 > > a/file.xz
76 > > a/b/
77 > > a/b/file
78 > > $ tar -tf test.tar.gz
79 > > a/
80 > > a/file.xz
81 > > a/b/
82 > > a/b/file
83 > >
84 > > You can find out the maximum length of the command-line with
85 > > `getconf ARG_MAX`.
86 >
87 >
88 > But does it work with a space instead of = as well? According to the
89 > online manual page, it should work both ways.
90 >
91
92 Yes. It also works with 10 spaces.
93
94 --
95 Get my PGP key with `gpg --locate-keys tastytea@××××××××.de` or at
96 <https://tastytea.de/tastytea.asc>.