GNU `tar` runs `stat` on an excluded directory. Is it normal?

Question

I'm running tar as root like this:

cd /
tar --create                    \
    --verify                    \
    --exclude-backups           \
    --exclude-caches            \
    --auto-compress             \
    --file /tmp/home.tar.gz     \
    --exclude=/home/elena/.gvfs \
    home

tar outputs:

tar: home/elena/.gvfs: Cannot stat: Permission denied

I would expect the .gvfs[1] directory to be ignored completely. Why is GNU tar running stat over it?

As to why I'm using /home/elena/.gvfs - an absolute path - to match the .gvfs directory, it is because - to my knowledge - there is no other way to select single directories for exclusion without excluding matching subdirectories at any level as well.

I've tried putting the --exclude line after home, to take possible quirks in different versions of tar into account, but that changes nothing.

Thanks for your attention.

GNU tar version: 1.23

--

[1] ~/.gvfs is a way to access the Gnome Virtual File System I'm skipping it because I know it can't be accessed, and it doesn't make sense to archive it. I still wonder why tar doesn't skip it completely.

@MattDMo: I have no idea: even `ls -l /home/elena/.gvfs` as **root** fails because of denied access. However, I know that `.gvfs` is a way to access the Gnome Virtual File System: http://en.wikipedia.org/wiki/GVFS I'm skipping it because I know it can't be accessed, and it doesn't make sense to archive it. — Eleno, Jul 12 '13 at 14:57
Try running `ls -al /home/elena` and let us know what the _entire_ `.gvfs` line says. This way, you're not trying to read the contents of `.gvfs` as `ls -l /home/elena/.gvfs` is doing. Also, can you read `/home/elena/.gvfs` as user `elena`, not `root`? — MattDMo, Jul 12 '13 at 17:22
Run as root, permission denied again: `ls: cannot access /home/elena/.gvfs: Permission denied`. And the `.gvfs` line reads: `d?????????? ? ? ? ? ? .gvfs` It's the only item in the output of `ls` that looks weird. — Eleno, Jul 12 '13 at 17:51
Are those question marks? Sorry, I'm on XP (Firefox 22) and what you posted just showed up as `d?????????? ? ? ? ? ?` (approximately, I just typed that in...) — MattDMo, Jul 12 '13 at 18:35

score 0 · Answer 1 · edited Jul 12 '13 at 14:45

0

tar: home/elena/.gvfs: Cannot stat: Permission denied

Notice that the error message doesn't include a leading slash. Try --exclude=home/elena/.gvfs without the slash.

edited Jul 12 '13 at 14:45

Karlson

5,845
32
51

answered Jul 12 '13 at 12:59

David Baggerman

2,154
20
11

Thank you, but I can't. Otherwise the pattern could match subdirectories at every level, and I don't want that. – Eleno Jul 12 '13 at 13:07
Then you can't exclude it. – tripleee Jul 12 '13 at 13:09
Hence `tar` doesn't allow for fine-grained control on what directories and files end up in an archive? – Eleno Jul 12 '13 at 13:26
Not by itself, as far as I understand the documentation. The workaround is to `find | grep - v stuff | xargs tar` or some approximation of that. – tripleee Jul 12 '13 at 14:23
2

@Elena Try also adding option `--anchored`. Than would match the initial part of the path name even without slash. – eppesuig Jul 12 '13 at 15:26
@eppesuig: Thanks, but I can't. The command in my question is not complete. The complete version needs to filter files in subdirectories based on their extension, and `--anchored` wouldn't allow that. Or am I allowed to mix `--anchored` and `--no-anchored` patterns? – Eleno Jul 12 '13 at 15:48
@Elena, yes you can mix `--anchored` and `--no-anchored`. The [example in the manual](https://www.gnu.org/software/tar/manual/html_node/controlling-pattern_002dmatching.html) uses `--ignore-case`, but it applies to `--anchored` and `--wildcards-match-slash` too. – cjm Jul 12 '13 at 16:10
@tripleee -- `| tar --files-from - ...` would work as well – sendmoreinfo Jul 12 '13 at 18:31
@sendmoreinfo: thanks for the tip; that's better than `xargs` actually. – tripleee Jul 12 '13 at 19:01

GNU `tar` runs `stat` on an excluded directory. Is it normal?

1 Answers1