Commands by vlan7

Commands by vlan7 (12)

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gag version of current date

Show Sample Output
This is sample output - yours may be different.
```
$date
Thu Dec  1 18:28:51 CET 2011
$ddate
Today is Setting Orange, the 43rd day of The Aftermath in the YOLD 3177
$ddate +%.
Hail Eris, Hack Linux!
$man ddate
```
5

ddate

vlan7 · 2011-12-01 17:33:04 8
Remount an already-mounted filesystem without unmounting it

Necessary for fsck for example. The remount functionality follows the standard way how the mount command works with options from fstab. It means the mount command doesn't read fstab (or mtab) only when a device and dir are fully specified. After this call all old mount options are replaced and arbitrary stuff from fstab is ignored, except the loop= option which is internally generated and maintained by the mount command. It does not change device or mount point.
This is sample output - yours may be different.
2

mount -o remount,ro /dev/foo /

vlan7 · 2010-10-30 03:51:53 7
Recover deleted Binary files

The above command assumes the lost data is on /dev/sda and you previously issued the following command to mount _another_ disk or partition (/dev/sdb1) on /recovery sudo mount /dev/sdb1 /recovery If you don't do this, the data could be overwrited! foremost is a very powerful carving tool. By default foremost recovers all known file types. If you want to reduce the amount of files that are recovered you can specify the file type you are looking for. Read the man page to know the available file types. i.e to recover JPEG pictures append to foremost the switch -tjpg
This is sample output - yours may be different.
2

sudo foremost -i /dev/sda -o /recovery

vlan7 · 2010-08-19 22:27:41 8
Show available conversions

aliases on each line. i.e. txt2html: recode ..HTML <file.txt >file.html txt to Base64: recode ../b64 <file.txt >file.b64 and so on.
This is sample output - yours may be different.
1

recode -l |less

vlan7 · 2010-08-19 17:35:23 5
untar undo
This is sample output - yours may be different.
3

tar tfz filename.tgz |xargs rm -Rf

vlan7 · 2010-07-31 14:39:21 6
Extract all of the files on an RPM on a non-RPM *nix
This is sample output - yours may be different.
4

rpm2cpio package.rpm |cpio -dimv

vlan7 · 2010-07-29 11:37:30 7
Show some trivia related to the current date

Contrary to logic, typing calendar won't show a calendar, that's the job of cal. Typing calendar will show some trivia related to the current date. Tested against many Linux distros and FreeBSD. Show Sample Output
This is sample output - yours may be different.
```
ene 29  N'oubliez pas les Gildas !
ene 29  Bonne fte aux Sulpice !
ene 30  Franklin Delano Roosevelt born in Hyde Park, New York, 1882
ene 30  Mohandas Gandhi assassinated in New Delhi by Hindu fanatic, 1948
ene 30  Tet Offensive, 1968
ene 30  Lightnin' Hopkins, the most-recorded blues artist ever, dies, 1982
ene 30  Aujourd'hui, c'est la St(e) Martine.
ene 30  Ernennung von Hitler zum Reichskanzler, 1933
```
6

calendar

vlan7 · 2010-01-29 11:17:11 7
Talk to the doctor (Eliza-like)

An easter-egg from emacs. Show Sample Output
This is sample output - yours may be different.
```
I am the psychotherapist.  Please, describe your problems.  Each time you are finished talking, type RET twice.

hello

How do you do?  What brings you to see me?
```
0

emacs <ESC+x> doctor

vlan7 · 2010-01-28 17:16:28 17
Get Cookies from bash

The loop is to compare cookies. You can remove it... Maybe you wanna use curl... curl www.commandlinefu.com/index.php -s0 -I | grep "Set-Cookie"
This is sample output - yours may be different.
3

a="www.commandlinefu.com";b="/index.php";for n in $(seq 1 7);do echo -en "GET $b HTTP/1.0\r\nHost: "$a"\r\n\r\n" |nc $a 80 2>&1 |grep Set-Cookie;done

vlan7 · 2010-01-28 14:19:43 12
Do some Perl learning...

Prerequisites: module Pod::Webserver installed. You can install it typing: sudo perl -MCPAN -e 'install Pod::Webserver' You can replace elinks with your fav browser. For FF: podwebserver& sleep 2; firefox -remote 'openurl( http://127.0.0.1:8020/, new-tab )' If you have Firefox open, this will pop-up the index web in a new tab.
This is sample output - yours may be different.
5

podwebserver& sleep 2; elinks 'http://127.0.0.1:8020'

vlan7 · 2010-01-27 10:57:34 14
Testing ftp server status

I must monitorize a couple of ftp servers every morning WITHOUT a port-scanner Instead of ftp'ing on 100 ftp servers manually to test their status I use this loop. It might be adaptable to other services, however it may require a 'logout' string instead of 'quit'. The file ftps.txt contains the full list of ftp servers to monitorize.
This is sample output - yours may be different.
1

for host in $(cat ftps.txt) ; do if echo -en "o $host 21\nquit\n" |telnet 2>/dev/null |grep -v 'Connected to' >/dev/null; then echo -en "FTP $host KO\n"; fi done

vlan7 · 2010-01-26 15:34:18 4
Fast tape rewind

Traditionally we rewind a tape using this syntaxis: mt -f /dev/rmt/0cbn rewind Redirecting the dispositive to nothing as shown above is faster. Less typing is always better.
This is sample output - yours may be different.
2

< /dev/rmt/0cbn

vlan7 · 2010-01-25 20:32:38 4

What's this?

commandlinefu.com is the place to record those command-line gems that you return to again and again. That way others can gain from your CLI wisdom and you from theirs too. All commands can be commented on, discussed and voted up or down.

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count how many cat processes are running

Unbelievable Shell Colors, Shading, Backgrounds, Effects for Non-X

I've been using linux for almost a decade and only recently discovered that most terminals like putty, xterm, xfree86, vt100, etc., support hundreds of shades of colors, backgrounds and text/terminal effects. This simply prints out a ton of them, the output is pretty amazing. If you use non-x terminals all the time like I do, it can really be helpful to know how to tweak colors and terminal capabilities. Like: $ echo $'\33[H\33[2J'

Find usb device in realtime

Using this command you can track a moment when usb device was attached.

Optimal way of deleting huge numbers of files

Optimal way of deleting huge numbers of files Using -delete is faster than: $ find /path/to/dir -type f -print0 | xargs -0 rm $ find /path/to/dir -type f -exec rm {} + $ find /path/to/dir -type f -exec rm \-f {} \;

Convert CSV to JSON

Replace 'csv_file.csv' with your filename.

delete a line from your shell history

If you're a moron like me, sometimes your fingers get away from you and you, for example, enter your password when you're already authenticated to ssh-agent, sudo, etc., and your password ends up in shell history. Here's how to get it out.

Process command output line by line in a while loop

This snippet allows to process the output of any bash command line by line.

Get the list of local files that changed since their last upload in an S3 bucket

Can be useful to granulary flush files in a CDN after they've been changed in the S3 bucket.

Configure a serial line device so you can evaluate it with a shell script

I had a hard time in finding the correct settings to get reasonable output from a coin selector which sends its data over a serial line. In the end, minicom came to the rescue and pointed me on the right track. So, if you need to do something similar, these settings may help you. Replace ttyUSB0 with your device file, 9600 with your baud rate, 5 with your read timeout (10ths of a second), and 1 with the minimum numbers of characters you want to read. You can then open the device file like you are used to do, example: $ DATA="`xxd -ps -l 5 \"$DEV\"`"

apt-get upgrade with bandwidth limit

in Debian-based systems apt-get could be limited to the specified bandwidth in kilobytes using the apt configuration options(man 5 apt.conf, man apt-get). I'd quote man 5 apt.conf: "The used bandwidth can be limited with Acquire::http::Dl-Limit which accepts integer values in kilobyte. The default value is 0 which deactivates the limit and tries uses as much as possible of the bandwidth..." "HTTPS URIs. Cache-control, Timeout, AllowRedirect, Dl-Limit and proxy options are the same as for http..."

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