Time Counter

Time Counter

Create a time counter using Shell scripting.

# Create a file  time.txt  in home folder (any folder is ok). put '0' (zero) in it as second (starting value of time).

time.txt

0

# Create a  time.sh  script (in the same folder) and put this code in it.

#!/bin/sh
#file: time.sh
#description: keep track of time spend on computer.

file=time.txt

if [[ -f $file ]]; then
old_time=$( cat $file ) && new_time=$[ $old_time + 60 ] && echo $new_time > $file ;
else
echo '0' > $file ;
fi;


This script will take stored time value from  time.txt  and add 60 seconds to it when run.
So if the current stored time value is '0' (zero), it will add 60 seconds to it. and so on.


# Now we will run this script with crontab. Open Terminal and edit crontab:

crontab -e

..and add this line to the bottom of the file:

* * * * * /bin/bash ~/time.sh

This will make the  time.sh  to run and update  time.txt  simulteneously every minute.


# put this code in .bashrc file (found in home folder). with this we can check the time on terminal..

counter() {
second=$( cat ~/time.txt ) ;
day=$[ $second/86400 ] ;
hour_remain=$[ $second%86400 ] ;
hour=$[ $hour_remain/3600 ] ;
minute_remain=$[ $second%3600 ] ;
minute=$[ $minute_remain/60 ] ;

echo $day days $hour hours $minute minutes since 2014 April 12th.
}

# Open Terminal and enter counter:

0 days 0 hours 44 minutes since 2014 April 12th.

Disclaimer:
Tutorial above is only for educative purposes. The author will not take liability for any damage caused to either software or hardware, by use, misuse or improper use of tutorial above.

update: 04th July 2020.

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netstat usage example

Sometimes we need to know who are connected to our system. this can be to find malware or botnet that may be connecting us to somewhere. or some trojan stealling our data. end point is we need to find out network activities. this can be done with 'netstat'.


running netstat command will display all connection in a unix system.

netstat



to find out all TCP connection with netstat.

netstat -t



to find out all TCP and UDP connection...

netstat -tu



to find out all connection initiated by a program through TCP..

netstat -tp



to output all information in numeric format..

netstat -n



to find out all incoming connection and listening to..

netstat -l



you can also combine them..

netstat -tn



this will output TCP connection in Numeric format.

netstat -tupn


this will output all connection made by a software program in Numeric format.


these above are few example of netstat. you can check out man page for more.


put this script inside your bash profile in /home/user/.bashrc

#!/bin/bash

connection()
{
cat=$( netstat -tun | sed '1,2 d' | awk '{print $5}' | sed -r 's/(.*)\:(.*)/\1/g' | sort | uniq );

for i in $cat; do
netname=$( whois $i | grep -i netname | awk '{print $2}' );
echo "connection with: $netname ($i)";
done;
}


now open 'terminal' and type 'connection'.

this is just one stupid script. you can build better than this.
godspeed.

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automate home folder backup and software install script

unix user is notorous for oftenly changing Operating System (OS) or distro hopping. since new/increment version are realeased more frequently. it become significant / necessary to update to a newer release.

installing and configuring is time consuming if you have lots of software to install, say 30 or more. even more if you spend time playing solitaire or 0AD (no i had not played 0AD yet).

the saving grace in this situation is to create a script that will automate this work. first backup/copy your home folder (along with hidden folder).

below is the script (bash) to automate install of software after fresh install of new OS (Operating system).
the script for backing up setting from home folder is given below.



#add the name of software you want to install here seperated by [space].

cd $HOME
app_list="firefox gcolor2 gimp vlc";

for app in $app_list; do
if [[ `which $app` == "" ]]; then
echo "installing $app.....";
apt-get -y install $app; #install the app
else
echo "$app is already installed (skipping)."; #app is already
installed
fi;
done;


#script for backing up setting (from home folder).

cd $HOME ;
folder=backup ;
mkdir $folder ;
dir=$HOME/$folder/ ;

for i in `ls -A`; do
if [[ $i == .* ]]; then
if ( [[ $i == .thumbnails ]] || [[ $i == .cache ]]
|| [[ $i == .gvfs ]] || [[ $i == .local ]]
) ; #add more folder name that you don't want to backup then echo "Not copied $i";
else
echo "Copying $i";
cp -r $i $dir$i ;
fi;
fi;
done;

tar -cf backup.tar ./$folder ;
rm -r ./$folder ;


ps- sorry for my bad english. i'm still new in scripting. this is my first post.