Commands using tar

If you want to decompress the files from an archive to current directory by stripping all directory paths, use --transform option to strip path information. Unfortunately, --strip-components option is good if the target files have same and constant depth of folders.

The idea was taken from http://www.unix.com/solaris/145941-how-extract-files-tar-file-without-creating-directories.html

This is freaking sweet!!! Here is the full alias, (I didn't want to cause display problems on commandlinefu.com's homepage):

Creates a .tgz archive of whatever directory it is run from, in the background, detached from current shell so if you logout it will still complete. Also, you can run this as many times as you want, if the archive .tgz already exists, it just moves it to a numbered backup '--backup=numbered'. The coolest part of this is the transformation performed by tar and sed so that the archive file names are automatically created, and when you extract the archive file it is completely safe thanks to the transform command.

If you archive lets say /home/tombdigger/new-stuff-to-backup/ it will create the archive /home/#home#tombdigger#new-stuff-to-backup#-2010-11-18.tgz Then when you extract it, like tar -xvzf #home#tombdigger#new-stuff-to-backup#-2010-11-18.tgz instead of overwriting an existing /home/tombdigger/new-stuff-to-backup/ directory, it will extract to /home/tombdigger/new-stuff-to-backup.2010-11-18/

Basically, the tar archive filename is the PWD with all '/' replaced with '#', and the date is appended to the name so that multiple archives are easily managed. This example saves all archives to your $HOME/archive-name.tgz, but I have a $BKDIR variable with my backup location for each shell user, so I just replaced HOME with BKDIR in the alias.

So when I ran this in /opt/askapache/SOURCE/lockfile-progs-0.1.11/ the archive was created at /askapache-bk/#opt#askapache#SOURCE#lockfile-progs-0.1.11#-2010-11-18.tgz

Upon completion, uses the universal logger tool to output its completion to syslog and stderr (printed to your terminal), just remove that part if you don't want it, or just remove the '-s ' option from logger to keep the logs only in syslog and not on your terminal.

Here's how my syslog server recorded this..

2010-11-18T00:44:13-05:00 gravedigger.askapache.com (127.0.0.5) [user] [notice] (logger:) Tarred /opt/askapache/SOURCE/lockfile-progs-0.1.11 to /askapache-bk/tarred/#opt#SOURCE#lockfile-progs-0.1.11#-2010-11-18.tgz in 4 seconds

Caveats

Really this is very robust and foolproof, the only issues I ever have with it (I've been using this for years on my web servers) is if you run it in a directory and then a file changes in that directory, you get a warning message and your archive might have a problem for the changed file. This happens when running this in a logs directory, a temp dir, etc.. That's the only issue I've ever had, really nothing more than a heads up.

Advanced:

This is a simple alias, and very useful as it works on basically every linux box with semi-current tar and GNU coreutils, bash, and sed.. But if you want to customize it or pass parameters (like a dir to backup instead of pwd), check out this function I use.. this is what I created the alias from BTW, replacing my aa_status function with logger, and adding $SECONDS runtime instead of using tar's --totals

{

local GZIP='--fast' PWD=${1:-`pwd`} F=$(date +${BKDIR}/%m-%d-%g-%H%M-`sed -u 's/[\/\ ]/#/g'

[[ ! -r "$PWD" ]] && echo "Bad permissions for $PWD" 1>&2 && return 2;

( ( tar --totals --ignore-failed-read --transform "s@^${PWD%/*}@`date +${PWD%/*}.%m-%d-%g`@S" -czPf $F $PWD && aa_status "Completed Tarp of $PWD to $F" ) & )

}

#From my .bash_profile http://www.askapache.com/linux-unix/bash_profile-functions-advanced-shell.html

The J option is a recent addition to GNU tar. The xz compression utility is required as well.

Same, but count of signs is little less :) .

A *.tar.gz file needs to be unzipped & then untarred. Previously I might have unzipped first with

and then untarred the result with

(Options are extract, verbose, file)

Using the -z (decompress) option on tar avoids the use of gzip (or gunzip) first.

Additionally the -C option will specify the directory to extract to.

This Anti-TarBomb function makes it easy to unpack a .tar.gz without worrying about the possibility that it will "explode" in your current directory. I've usually always created a temporary folder in which I extracted the tarball first, but I got tired of having to reorganize the files afterwards. Just add this function to your .zshrc / .bashrc and use it like this;

and it will create a folder for the extracted files, if they aren't already in a single folder.

This only works for .tar.gz, but it's very easy to edit the function to suit your needs, if you want to extract .tgz, .tar.bz2 or just .tar.

More info about tarbombs at http://www.linfo.org/tarbomb.html

Tested in zsh and bash.

UPDATE: This function works for .tar.gz, .tar.bz2, .tgz, .tbz and .tar in zsh (not working in bash):

UPDATE2: From the comments; bepaald came with a variant that works for .tar.gz, .tar.bz2, .tgz, .tbz and .tar in bash:

Simplicity tends to win out on commandlinefu.com Also, why type multiple filenames when range operators work too. Saves finger abuse and time and reduces the chances for mistakes.

tar doesn't support wildcard for unpacking (so you can't use tar -xf *.tar) and it's shorter and simpler than

for i in *.tar;do tar -xf $i;done (or even 'for i in *.tar;tar -xf $i' in case of zsh)

-i says tar not to stop after first file (EOF)

Using the COPYFILE_DISABLE=true environment variable you can prevent tar from adding any ._-files to your .tar-file on Mac OS X.

The following command finds all the files not modified in the last 5 days under /protocollo/paflow directory and creates an archive files under /var/dump-protocollo in the format of ddmmyyyy_archive.tar

This is a shortcut to tar up all files matching a wildcard. Tar doesn't have the --include (apparently).

if I need get olnly script.sh from "folder/script.sh"

You don't need to create an intermediate file, just pipe the output directly to tar command and use stin as file (put a dash after the f flag).

Requires the GNU tar ignore zeros option. http://www.gnu.org/software/tar/manual/html_section/Blocking.html