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 2
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 8

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 2

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.)
```
34

[enter]~?

xeor · 2011-06-17 18:29:59 48
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 3
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 2
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 2
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 7
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 5
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 5
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 3
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 19
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 2
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 2
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 7

What's this?

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list block devices

Shows all block devices in a tree with descruptions of what they are.

Which processes are listening on a specific port (e.g. port 80)

swap out "80" for your port of interest. Can use port number or named ports e.g. "http"

Watch active calls on an Asterisk PBX

Works on asterisk 1.8.

Convert CSV to JSON

Replace 'csv_file.csv' with your filename.

create a backup for all directories from current dir

Create backup (.tar.gz) for all first-level directory from current dir.

Monitor a file with tail with timestamps added

Should be a bit more portable since echo -e/n and date's -Ins are not.

Which processes are listening on a specific port (e.g. port 80)

swap out "80" for your port of interest. Can use port number or named ports e.g. "http"

Top 10 Memory Processes

It displays the top 10 processes sorted by memory usage

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.

Use a var with more text only if it exists

See "Parameter Expansion" in the bash manpage. They refer to this as "Use Alternate Value", but we're including the var in the at alternative.

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Commands by xeor (15)

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