this post was submitted on 29 Jun 2024
31 points (100.0% liked)

Linux

47923 readers
1307 users here now

From Wikipedia, the free encyclopedia

Linux is a family of open source Unix-like operating systems based on the Linux kernel, an operating system kernel first released on September 17, 1991 by Linus Torvalds. Linux is typically packaged in a Linux distribution (or distro for short).

Distributions include the Linux kernel and supporting system software and libraries, many of which are provided by the GNU Project. Many Linux distributions use the word "Linux" in their name, but the Free Software Foundation uses the name GNU/Linux to emphasize the importance of GNU software, causing some controversy.

Rules

Related Communities

Community icon by Alpár-Etele Méder, licensed under CC BY 3.0

founded 5 years ago
MODERATORS
 

This is bothering me for years now, my backup script always takes everything with it, taking forever to finish.

I initially used the --exclude option, but this is rather restrictive, cluttered the script and still had the excluded directories.
Then i discovered -X/--exclude-from but same result here, weird globbing and still fails.
So i hacked a negative list via fd's --ignore-file and tar -T/--files-from together. But tar still includes files and directories not on the fucking files.tmp.

So i'm not sure if it is a bug in Arch's GNU tar or if it's maybe a parameter in the wrong position, tar can be removed there. This is my current code

# tar -cf - -X "$XDG_CONFIG_HOME"/backup/ignore "$INPUT" -P

fd . -Hi --ignore-file "$XDG_CONFIG_HOME"/backup/ignore "${INPUT}" > "$_tmpfile"
tar -cf - --verbatim-files-from --files-from="$_tmpfile" -P \
	|pv -tapes "$_fssize" \
	|compress >"${OUTPUT}.$_ext"

INPUT is $HOME in this case.

And if anyone has a solution that works on busybox tar as well...

all 6 comments
sorted by: hot top controversial new old
[–] lurch@sh.itjust.works 9 points 4 months ago

--exclude works reliable for me. can you give us an example of an --exclude and the file name that tar outputs when adding it?

[–] kbal@fedia.io 4 points 4 months ago* (last edited 4 months ago) (1 children)

I don't know what fd does, but at a guess maybe what you're missing is that tar includes all the files in directories you give it? So if you exclude 'foo/bar' but include 'foo' then foo/bar will be in your tar file.

What I do is basically tar cf `ls ~ | grep -v $files_to_exclude` but if you want to exclude something that isn't a top-level directory you'd need to get slightly more fancy.

[–] kbal@fedia.io 1 points 4 months ago* (last edited 4 months ago)

...more fancy such as using tar -X, which works for me. I'd never actually tried it before. The 'weird globbing' it uses is regular expressions, which are worth learning how to use. Run grep "$expression" $_tmpfile where $expression is a line from your exclude file to see which files it's going to match and exclude.

[–] MonkderDritte@feddit.de 2 points 4 months ago* (last edited 4 months ago)

Thanks!

I save it for now, until i work on it again. Possibly the wildcards thing. And that tar includes files of folders given too, from someone else (how to work with that).

[–] TCB13@lemmy.world -4 points 4 months ago

How to reliably(!) exclude files from a list in tar?

You delete the entire file because the format and tools are hard to deal with for basic operations like this one. :)

Just kidding... but we know there's some truth to it.