Re: [Bug-tar] --no-overwrite-dir implies that tar will overwrite files w
From:
Remi Broemeling
Subject:
Re: [Bug-tar] --no-overwrite-dir implies that tar will overwrite files when extracting?
Date:
Thu, 6 Aug 2015 15:42:06 -0600
Re-send, as my "send" hotkey was trigger-happy on the last message (please disregard the previous).
Hi all -- have run into this bit of weirdness today, and I was hoping someone here could either confirm it as a bug or tell me how I am utterly confused about how these options function. My intent is to extract an archive onto the local system and to never overwrite or otherwise modify existing files (i.e. to "fill in the blanks" onto the local system by extracting missing files out of an archive).
I'm attempting to do this with a command like this:
tar --bzip2 --extract --file "${ARCHIVE}" --keep-old-files --no-overwrite-dir --preserve-order --preserve-permissions
... this command overwrites any existing files with old versions from the archive, however (which is the opposite of what I would expect).
Playing around on my local system I was able to replicate this behavior:
$ mkdir tar-test
$ cd tar-test/
$ echo ARCHIVE_DATA>FILE
$ cat FILE
ARCHIVE_DATA
$ tar cf /tmp/tar-test.tar *
$ rm FILE
$ tar xf /tmp/tar-test.tar
$ cat FILE
ARCHIVE_DATA
$ echo NEW_DATA >FILE
$ cat FILE
NEW_DATA
$ tar xf /tmp/tar-test.tar # This should overwrite the file.
$ cat FILE
ARCHIVE_DATA
$ echo NEW_DATA >FILE
$ cat FILE
NEW_DATA
$ tar kxf /tmp/tar-test.tar # This should NOT overwrite the file.
$ cat FILE
NEW_DATA
$ tar kxf /tmp/tar-test.tar --no-overwrite-dir # This should NOT overwrite the file, but it does.
$ cat FILE
ARCHIVE_DATA
All of this is with Debian's oldstable version of tar:
This is free software: you are free to change and redistribute it.
There is NO WARRANTY, to the extent permitted by law.
Written by John Gilmore and Jay Fenlason.
Is anyone able to lend some clarity as to what exactly is going on and why adding --no-overwrite-dir is causing tar to overwrite files that it explicitly shouldn't?