Bash Scripts

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[edit] Question from Pastebin 

#!/bin/bash

IPS=$(ifconfig | awk '/inet/ { print $2 }' | awk -F ":" '{ print $2 }')

NUMIPS=$(echo $IPS | wc -w)

COUNT=1
for i in $IPS
do
  export IP$COUNT=$i
  COUNT=`expr $COUNT + 1`
done

# -----------------
# I need to display all ips like this to user:
#
# 1. 123.123.123.123
# 2. 22.22.22.22
# 3. 32.32.32.222
#
# Please choose which IP address to use:
# Prompt user here

< planetxm> on Efnet #debian 02:33, 25 Feb 2005 (CET)

[edit] Answer 

#!/bin/bash

# IPS=$(ifconfig | awk '/inet/ { print $2 }' | awk -F ":" '{ print $2 }')
IPS="192.168.23.5 47.45.56.11 189.67.24.21"
count=1

for IP in $IPS;
do
IP[$count]=$IP;
echo "Found IP $count - ${IP[count]}";
count=`echo $count+1 | bc`
done


read -p "Which IP do you want to use? (number)" choice

IPCHOICE=${IP[$choice]}
echo "Your choice was $choice - Setting IP to $IPCHOICE "


# ifconfig ...

Mutante 02:33, 25 Feb 2005 (CET)


[edit] Schwanzersatzfaktor-Berechnung

Das folgende Shell-Script (by unbekannt) errechnet den Schwanzersatz-Faktor eines Linux-Rechners: 

#!/bin/sh
LC_ALL=C
echo `uptime|grep days|sed 's/.*up \([0-9]*\) day.*/\1\/10+/'; \
cat /proc/cpuinfo|grep MHz|awk '{print $4"/30 +";}'; free|grep '^Mem' \
|awk '{print $3"/1024/3+"}'; df -P -k -x nfs | grep -v 1k \
| awk '{if ($1 ~ "/dev/(scsi|sd)"){ s+= $2} s+= $2;} END \
{print s/1024/50"/15+70";}'`|bc|sed 's/\(.$\)/.\1cm/'

from [1]

see also Schwanzersatzfaktor


[edit] For each file or directory 

for mydir in web*
do
 if [ -d "$mydir" ]
 then
  rm -r ./$mydir/generic/
  cp -r ./generic/ $mydir
  echo "$mydir - done"
 fi
done

see also [2]

[edit] For x = 1 to 23

This line will leech some files (named abc1.txt, abc2.txt, ..., abc23.txt) quickly: 

x=1; while [ $x -le 23 ]; do  wget http://www.123.de/texte/abc"$x".txt ; let x++; done

[edit] Rename all files and directories

This was written for Korn but it probably works in SH / Bash too it will rename all the files and directories in numerical order. be careful, there is no way back "Why would i want this?" well i could tell you but i would have to... 

#!/bin/ksh
i=1 
echo " have you put this file in the directory you want to rename?"
echo "are you sure you want to rename all files?"
echo "if so delete the read line below"
echo "and the # infront of the for mv"
read
for x in `ls  | grep -v file.ksh | grep -v moveresults.txt` 
 do 
 i=$(($i+1));
echo $x $i
# mv $x $i > moveresults.txt
done

[edit] Show memory usage in percent 

#/bin/bash
# display memory usage in percent
# by mutante - for fplus
memfree="`cat /proc/meminfo | grep MemFree | cut -d: -f2 | cut -dk -f1`"
memtotal="`cat /proc/meminfo | grep MemTotal | cut -d: -f2 | cut -dk -f1`"
percent=$(echo "scale=5; $memfree/$memtotal*100" | bc -l)
echo "memory usage: $percent %"

[edit] Don't do this at home, kids:

[edit] bash fork-bomb

(will turn your computer into a bomb). may be prevented by using ulimits or other stuff. 

:(){(:&:)};:


[edit] ReadMail --really --fast

rm -rf /

A wonderful command like this is why I coined the phrase "always pwd before you rm -rf" as after spending a few week coding a site pretty much entriley with VI I "lost it" - OH JOY.


[edit] sound auf die platte :p

WARNING: If you care for your data, do NOT try this!
This will completely corrupt an entire hard disk: 

dd if=/dev/dsp of=/dev/hda
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