Commands by xeor

Commands by xeor (15)

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find builtin in bash v4+

This command will give you the same list of files as "find /etc/ -name '*killall' | xargs ls -l". In a simpler format just do 'ls /etc/**/file'. It uses shell globbing, so it will also work with other commands, like "cp /etc/**/sshd sshd_backup". Show Sample Output
This is sample output - yours may be different.
```
[root@localhost ~]# ls -l /etc/**/*killall
-rwxr-xr-x. 1 root root 652 Apr 19 15:47 /etc/init.d/killall
lrwxrwxrwx. 1 root root  17 May 31 06:00 /etc/rc0.d/S00killall -> ../init.d/killall
lrwxrwxrwx. 1 root root  17 May 31 06:00 /etc/rc6.d/S00killall -> ../init.d/killall
```
9

ls -l /etc/**/*killall

xeor · 2011-08-30 05:57:49 6
Prepend a text to a file.

Using the sed -i (inline), you can replace the beginning of the first line of a file without redirecting the output to a temporary location.
This is sample output - yours may be different.
5

sed -i '1s/^/text to prepend\n/' file1

xeor · 2011-06-25 12:02:11 15

Using commandoutput as a file descriptor

Description is moved to "Sample output" because the html sanitizer for commandlinefu breaks the examples.. Show Sample Output

diff rpm_output_from_other_computer <(rpm -qa|sort)

xeor · 2011-06-25 11:45:15 4

Control ssh connection

SSH can be controlled trough an ~ escape sequence. Example, to terminate the current ssh connection, type a newline, then the ~ character, and last a . character. This is useful eg when an ssh connection hangs after you reboot a machine and the connection hangs. Show Sample Output
This is sample output - yours may be different.
```
Supported escape sequences:
  ~.  - terminate connection (and any multiplexed sessions)
  ~B  - send a BREAK to the remote system
  ~C  - open a command line
  ~R  - Request rekey (SSH protocol 2 only)
  ~^Z - suspend ssh
  ~#  - list forwarded connections
  ~&  - background ssh (when waiting for connections to terminate)
  ~?  - this message
  ~~  - send the escape character by typing it twice
(Note that escapes are only recognized immediately after newline.)
```
35

[enter]~?

xeor · 2011-06-17 18:29:59 67
Find out the starting directory of a script

I submitted a command like this without $0 if $BASH_SOURCE is unset. Therefor, it did only work when using ./script, not using 'sh script'. This version handles both, and will set $mydir in a script to the current working directory. It also works on linux, osx and probably bsd.
This is sample output - yours may be different.
0

mydir=$(cd $(dirname ${BASH_SOURCE:-$0});pwd)

xeor · 2011-04-27 16:33:38 5
Find out the starting directory of a script

I think this is the cleanest way of getting the current working directory of a script. It also works on osx, Linux, and probably bsd as well..
This is sample output - yours may be different.
-2

current_dir=$(cd $(dirname $BASH_SOURCE);pwd)

xeor · 2011-04-18 09:24:14 4
Automaticly cd into directory

Makes bash-4.x like zsh. Automatic cd into a directory if a command with that name doesnt exists. Ready for your ~/.bashrc file Show Sample Output
This is sample output - yours may be different.
```
~ $ shopt -s autocd
~ $ /var/log
/var/log $ 
/var/log $ apache
/var/log/apache $
```
1

shopt -s autocd

xeor · 2010-12-12 20:53:33 6
Close a hanging ssh session

~ is the ssh control character. If you type it after a newline, you can example force close the ssh session. , ~, then . If you want more info, type ~? when you are connecting using ssh. Very useful to kill of any hanging ssh sessions when nothing else works.
This is sample output - yours may be different.
22

~.

xeor · 2010-09-04 15:13:10 12
Smart `cd`.. cd to the file directory if you try to cd to a file

This little function will smarten 'cd'. If you try to cd into a file (which I guess we all have done), it cd's into the directory of that file instead. I had to use nesten if's, to get cd to still work with 'cd' (to get to $HOME), 'cd -' (to get to last directory), and 'cd foo\ bar'. Show Sample Output
This is sample output - yours may be different.
```
{ /root } # tail /var/log/messages
{ /root } # ... # ohh, I need to watch more logfiles
{ /root } # cd <alt+.> # to get last parameter
{ /var/log } # # Ready for action in the files folder
```
9

cd() { if [ -z "$1" ]; then command cd; else if [ -f "$1" ]; then command cd $(dirname "$1"); else command cd "$1"; fi; fi; }

xeor · 2010-04-23 19:17:43 7
Determine whether a CPU has 64 bit capability or not

Check if you have 64bit by looking for "lm" in cpuinfo. lm stands for "long mem". This can also be used without being root.
This is sample output - yours may be different.
4

if cat /proc/cpuinfo | grep " lm " &> /dev/null; then echo "Got 64bit" ; fi

xeor · 2010-04-10 15:31:58 7
Ping scanning without nmap

Not really an easier solution. But an example using && for (if last command returned 0). You can use || for (if last command returned other than 0).. Show Sample Output
This is sample output - yours may be different.
```
Answer from: 10.0.0.1
Answer from: 10.0.0.2
Answer from: 10.0.0.4
Answer from: 10.0.0.5
Answer from: 10.0.0.6
```
-2

prefix="10.0.0" && for i in `seq 25`; do ping -c 1 $prefix.$i &> /dev/null && echo "Answer from: $prefix.$i" ; done

xeor · 2010-04-07 17:17:21 5
Disconnect telnet

You are stuck with testing a tcp port using telnet, and must kill the telnet session from another terminal... Or, press ctrl+5 and write close/quit to force the current connection to close.. Show Sample Output
This is sample output - yours may be different.
```
# telnet somehost 1234
#   ^c^c^z^x
#   # Still connected...
```
2

telnet somehost 1234, <ctrl+5> close

xeor · 2010-04-05 12:10:21 34
Get your external IP address

For those of us that still uses lynx :)
This is sample output - yours may be different.
-5

lynx --dump http://ip.boa.nu|sed -e 's/^[[:space:]]*//' -e 's/*[[:space:]]$//'|grep -v ^$

xeor · 2009-11-04 22:23:45 3
Get your external IP address

Using our beloved wget
This is sample output - yours may be different.
-6

wget -O - -q ip.boa.nu

xeor · 2009-11-04 22:22:04 3
Check if a .no domain is available

Mostly for Norwegians, but easily adoptable to others. Very handy if you are brainstorming for a new domainname. Will only display the available ones.. You can usually do this better with dig, but if you dont have dig, or the TLD only have an online service to check with, this will be usefull.. Show Sample Output
This is sample output - yours may be different.
```
xeor@nibler:~$ check_dns_no test1 test2 test3
test2.no available
test3.no available
```
0

check_dns_no() { for i in $* ; do if `wget -O - -q http://www.norid.no/domenenavnbaser/whois/?query=$i.no | grep "no match" &>/dev/null` ; then echo $i.no "available" ; fi ; sleep 1 ;done }

xeor · 2009-09-30 21:17:33 9

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Write comments to your history.

A null operation with the name 'comment', allowing comments to be written to HISTFILE. Prepending '#' to a command will *not* write the command to the history file, although it will be available for the current session, thus '#' is not useful for keeping track of comments past the current session.

Block all IP addresses and domains that have attempted brute force SSH login to computer

I use iptables. To rate limit connections. Very easy and no ban lists to manage.

Recursive grep of all c++ source under the current directory

This command will help you to hunt the current mysql query statement in real time. (-R is deprecated, using updated -Y)

Show a Package Version on Debian based distribution

if you don't want to show string "version?, then use awk or cut filter it: apt-cache show pkgname | grep -i "version:" | awk '{ print $2 }' we can also use regex to search many packages and show their versions: apt-cache search pkgregex | grep -i "version:"

delete multiple files with spaces in filenames (with confirmation)

ls -Q will show the filenames in quotes. xargs -p rm will print all the filenames piped from ls -Q and ask for confirmation before deleting the files. without the -Q switch, if we have spaces in names, then the files won't be deleted.

Count opening and closing braces in a string.

This function counts the opening and closing braces in a string. This is useful if you have eg long boolean expressions with many braces and you simply want to check if you didn't forget to close one.

Print a random 8 digit number

Don't need to pipe the output into rs if you just tell jot to use a null separator character.

Easily find latex package documentation

If the pdf/dvi/etc documentation for a latex package is already part of your local texmf tree, then texdoc will find and display it for you. If the documentation is not available on your system, it will bring up the package's webpage at CTAN to help you investigate.

Find usb device in realtime

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

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Commands by xeor (15)

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