QuadKonsole – Programme Better

Well, the era of Quad Core computing is approaching fast. But everybody can’t just enjoy the computing powers of those high end processors due to very high cost and maintenance(power supply and heat) problems. If you are a programmer and and use linux, then you can at least have a Quad Core Konsole. I found a small application here which can change the way you program and can make programming very easy and fast. It has four konsoles tiled in one single window and comes with very easy navigation controls. You may want to give it a try. Below is a screenshot of QuadKonsole.

Quad Core Konsole

Quad Core Konsole

 

Hack: Mange Fluctuating Wireless

I am trying this small script with a so called gui 😉 . This helps managing my wireless in the extreme conditions. Just a shell script. Run the script as root otherwise it’ll not work.

Get the script here or copy the code below.

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#!/bin/bash
#
#	Author - Kulbir Saini, IIIT Hyderabad.
#	Home - http://saini.co.in/
#	KWirelessManger - Just for fun.(It works ... its not just fun).
#
 
#Give the popup life.
POPUP_LIFE="10"
#kdialog --passivepopup "Welcome to 'KWirelessManager'"  ${POPUP_LIFE} &
#Give your device name for proceeding further. It may be one of wlan0, ra0, eth0, ipw2200 etc...
WLAN_DEVICE="wlan0"
#Give your WLAN host to be connected.
WLAN_HOST="IIIT WLAN"
CONNECTED=0
while [[ 1 ]];
do
	iwlist ${WLAN_DEVICE} scanning 2> /dev/null > /tmp/iwlist.aps
	grep -e "Cell" /tmp/iwlist.aps | tr " " "\t" | cut -f15 > /tmp/iwlist.apadd
	ACCESS_POINTS_IN_RANGE=`wc -l /tmp/iwlist.apadd`
	for ACCESS_POINT_ADDRESS in `cat /tmp/iwlist.apadd`
	do
		iwconfig ${WLAN_DEVICE} ap ${ACCESS_POINT_ADDRESS}
		#kdialog --passivepopup "Connceting to Access Point ${ACCESS_POINT_ADDRESS} ..." ${POPUP_LIFE} &
		echo "Connceting to Access Point ${ACCESS_POINT_ADDRESS} ..."
		WLAN_STATUS=`service network restart | tail -1 | grep "FAILED"`
		if [[ ${WLAN_STATUS} == "" ]];
		then
			#kdialog --passivepopup "You are connected to ${WLAN_HOST}." ${POPUP_LIFE} &
			echo "You are connected to ${WLAN_HOST}."
			CONNECTED=1
			break
		else
			#kdialog --passivepopup "Failed to connect to the Access Point ${ACCESS_POINT_ADDRESS} :(" ${POPUP_LIFE} &
			echo "Failed to connect to the Access Point ${ACCESS_POINT_ADDRESS} :("
			CONNECTED=0
		fi
	done
	if [[ ${CONNECTED} == 1 ]];
	then
		sleep 180;
	fi
done

Please suggest any optimization and do tell if u like it.

 

Hack: Mail Filter – Shell Script

This is an attempt by me to filter mails on a Linux machine. You can run this file on your home directory at mail server and it will help you to sort mails on the basis of

  • From which user the mail has come or from which domain it came,
  • to which user or domain mail was sent and
  • the keywords in the subject part of the mail.

Actually its very slow as shell is very slow , I cant help it . It scan your entire mbox file in the home directory by default. Copy the code and paste in a file say filter.sh and change its permissions to executable. Place it in you home directory at the mail server and run.

Example
You want to see all mails from username@gmail.com just run and it will ask for input,
press 1
From: username [Enter]
It will display all the mails from that are lying there in your mbox one by one.

Get the script here or copy the code below.

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#!/bin/bash
#################################
#   Author - Kulbir Saini       #
#   Home - http://sain.ico.in/  #
#################################
 
#shell script to filter mails.
echo -e -n "\033[32mWelcome to the mail filter system \nWhat do you want to do? \nCheck mails on basis of \n1) Sender... \n2) Receiver... \n3) Subject... \n4) Quit... \nPress(1,2,3,4): \033[0m"
read int <&2
while [[ 1 ]];do
while [[ 1 ]];do
count=0;	line=""
if [[ $int == 1 ]];then
	echo -n -e "\033[32mFrom:\033[0m "
	read from <&2
	i=0
	clear
	while read line ;do
	loopbreak=0;	nextmessagestatus=1;	mailtostatus=1;		mailsubstatus=1;	stat=1;
	toecho=`echo $line | grep -E "^From:+" | grep -E "${from}"`
	if [ "$toecho" != "" ];then
		i=`expr $i + 1`
		echo -e "${toecho}"
		while read line ; do
		mailto=`echo $line | grep -E "^To:+"`
		mailsub=`echo $line | grep -E "^Subject:+"`
		if [[ "$mailto" != "" ]] && [[ $mailtostatus == 1 ]];then
			echo $mailto
			mailtostatus=0
		fi
		if [[ "$mailsub" != "" ]] && [[ $mailsubstatus == 1 ]];then
			echo $mailsub
			mailsubstatus=0
		fi
		if [[ $mailtostatus == 0 ]] && [[ $mailsubstatus == 0 ]] && [[ $stat == 1 ]];then
			echo -e "\033[33mStarting of the Message${i}:\033[0m"
			stat=0
		fi
		fromstatus=`echo $line | grep -E "^X-UID:+"`
			if [[ $fromstatus != "" ]];then
			while read line; do
				loopstatus=`echo $line | grep -E "^From +"`
				if [[ $loopstatus != "" ]];then
				loopbreak=1
				break
				fi
				echo $line
			done
			if [[ $loopbreak == 1 ]];then
			echo -e -n "\033[33mEnd of the Message${i}.\nDisplay next message(y/n):\033[0m"
			read messagestatus <&2
			if [[ "$messagestatus" == "y" ]];then
				clear
			else
				nextmessagestatus=0
			fi
			break
			fi
			fi
		done
		count=`expr $count + 1`
	fi
	if [[ $nextmessagestatus == 0 ]];then
		break
	fi
	done
	if [[ $count == 0 ]];then
		echo -e "\033[32mNo mail(s) From: ${from}.\n\033[0m"
	else
		echo -e "\033[32mTotal $count mail(s) From: ${from}.\n\033[0m"
	fi
elif [[ $int == 2 ]];then
	echo -n -e "\033[32mTo: \033[0m"
	read to <&2
	i=0
	clear
	while read line ;do
	loopbreak=0;	nextmessagestatus=1
	toecho=`echo $line | grep -E "^To:+" | grep -E "${to}"`
	if [[ "$toecho" != "" ]];then
		echo -e "$toecho"
		i=`expr $i + 1`
		while read line; do
			tostatus=`echo $line | grep -E "^X-UID:+"`
			if [[ $tostatus != "" ]];then
			echo -e "\033[33mStarting of the Message${i}:\033[0m"
			while read line; do
				loopstatus=`echo $line | grep -E "^From +"`
				if [[ $loopstatus != "" ]];then
				loopbreak=1
				break
				fi
				echo $line
			done
			if [[ $loopbreak == 1 ]];then
			echo -e -n "\033[33mEnd of the Message${i}. \nDisplay next message(y/n): \033[0m"
			read messagestatus <&2
			if [[ $messagestatus == "y" ]];then
				clear
			else
				nextmessagestatus=0
			fi
			break
			fi
			fi
		done
		count=`expr $count + 1`
	fi
	if [[ $nextmessagestatus == 0 ]];then
		break
	fi
	done
	if [[ $count == 0 ]];then
		echo -e "\033[32mNo mail(s) to: ${to}.\n\033[0m"
	else 
		echo -e "\033[32mTotal $count mail(s) To: ${to}.\n\033[0m"
	fi
elif [[ $int == 3 ]];then
	echo -n -e "\033[32mSubject:\033[0m "
 
	read subject <&2
	clear
	i=0
	while read line ;do
	loopbreak=0;	nextmessagestatus=1
	toecho=`echo $line | grep -E "^Subject:+" | grep -E "${subject}"`
	if [[ "$toecho" != "" ]];then
		echo "$toecho"
		i=`expr $i + 1`
		while read line; do
		substatus=`echo $line | grep -E "^X-UID:+"`
		if [[ $substatus != "" ]];then
		echo -e "\033[33mStarting of the Message${i}:\033[0m"
		while read line ; do
			loopstatus=`echo $line | grep -E "^From +"`
			if [[ $loopstatus != "" ]];then
			loopbreak=1
			break
			fi
			echo $line
		done
		if [[ $loopbreak == 1 ]];then
		echo -e -n "\033[33mEnd of the message${i}. \nDisplay next message(y/n): \033[0m"
		read messagestatus <&2
		if [[ $messagestatus == "y" ]];then
			clear
		else
			nextmessagestatus=0
		fi
		break
		fi
		fi
		done
		count=`expr $count + 1`
	fi
	if [[ $nextmessagestatus == 0 ]];then
		break
	fi
	done
	if [[ $count == 0 ]];then
		echo -e "\033[32mNo mail(s) with Subject: ${subject}.\n\033[0m"
	else
		echo -e "\033[32mTotal $count mail(s) with Subject: ${subject}.\033[0m\n"
	fi
elif [[ $int == 4 ]];then
	echo -e "\033[32mThank you for using this utility. \nPlease visit again.\033[0m"
	exit
else
	echo -e "\033[32mI could not understand that. \nPlease try again.\033[0m\n"
fi
echo -e -n "\033[32m1) Sender... \n2) Receiver... \n3) Subject... \n4) Quit... \nPress(1,2,3,4):\033[0m "
read int <&2
break
done < mbox 
done
 

How To: Troubleshoot SCP Command

Some times we face problems in transferring the data from one machine to other machine using scp. Actually the scp command is executed successfully but the data is not transferred. As the .bashrc and not the .bash_profile file of the system to which the data is being transferred is executed. If the .bashrc of the remote system contains any command or executable which output some data to the standard output then that command is executed and the output is flushed on the local machine and the scp command is terminated and data is not transferred.

For example if the remote machine has any ‘echo’ or ‘nfrm’ command in .bashrc file, the scp of the data will not be possible.
Also suppose the remote machine has a lines in .bashrc like this

./test.sh

where test.sh contains the data as below:-

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#/usr/bin/sh
echo "Kulbir Saini"

Then also the scp will not be possible.

So if you are facing such problems please try to remove such lines from your .bashrc file and scp the data you want.
Anyway you can keep those lines in your .bash_profile because it is not executed while transferring the data.

Please report any other cases in which scp is not possible.

 

How To: Yahoo Messenger on Teaching Lab Machines

Though the pcs in the labs are not having any support for applications except terminal or command line, Linux version of yahoo messenger can be opened there. This is a step by step procedure.

Step 1

Open two terminals and through one of them logon on to your mirage server account because that supports the Gaim(Linux version of yahoo messenger).

Step 2

Now I will call the terminal in which you are logged into mirage as remote machine and the terminal of the machine at which you are working as local machine.
At your local machine execute these commands.

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[kulbir@localhost ~] xhost + [Enter]
access control disabled, clients can connect from any host

The messege displayed above should appear otherwise you may have problems.

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[kulbir@localhost ~] /sbin/ifconfig [Enter]
eth0      Link encap:Ethernet  HWaddr 00:11:2F:57:C5:9D
inet addr:372.12.226.25  Bcast:122.12.226.123  Mask:212.223.345.138
UP BROADCAST RUNNING MULTICAST  MTU:1520  Metric:1
RX packets:136851 errors:0 dropped:0 overruns:0 frame:0
TX packets:82928 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:1000
RX bytes:71106959 (67.8 Mb)  TX bytes:40997603 (39.0 Mb)
Interrupt:10
lo        Link encap:Local Loopback
inet addr:122.4.4.1  Mask:252.2.2.1
UP LOOPBACK RUNNING  MTU:11436  Metric:1
RX packets:46123 errors:0 dropped:0 overruns:0 frame:0
TX packets:46123 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:0
RX bytes:22001021 (20.9 Mb)  TX bytes:22001021 (20.9 Mb)

The address against inet_addr in 3rd line is the IP address of your local machine.

Step 3

Now switch to your remote machine terminal and issue the following commands…

[kulbir@server ~] export DISPLAY=[IP address]:0.0  [Enter]

e.g.

[kulbirsaini@server ~] export DISPLAY=222.26.36.5:0.0 [Enter]

If no error comes, means things are going fine.

[kulbir@server ~] xterm [Enter]

Now also if no error comes and a new teminal appears then you are ready to open the gaim.
Issue this command on the new appeared terminal

[kulbir@server ~] gaim [Enter]

yahoo messenger will appear and now you are ready to chat.
Add your account to the messenger and chat 😀