Debian commands

To have alternate versions of the same program like matlab, java, etc
man 8 update-alternatives
/usr/sbin/update-alternatives --list matlab


To install a new font (true type) put the font in /usr/share/fonts/truetype/ (in debian) and run
fc-cache -fv
then restart X ( /etc/init.d/gdm restart if using GNOME display manager)


To sort folders in current directory by size
du --max-depth=1 ./ | sort -n -r

Some good technical links

For fixing NTFS not mounting in Linux (Debian) check this link :http://ubuntuforums.org/showthread.php?t=656025&page=2

how to install any package in latex

create a texhash directory in home folder. download the package say "latex-beamer.ter.gz" to a folder inside the texmf/ tree.say "texmf/latex/beamer/". now all the contents of the package should be put in this directory.
Then run "texhash" for latex to find these files.

if you have any dtx file in the package like for eg. "empheq.dtx" then you need to run "tex empheq.dtx" to create the runtime environment files.

wireless cards supported on linux

REFERRED FROM : http://sushant354.blogspot.com/2007/02/wireless-card-supported-for-linux.html

Linux limited support for wireless devices makes one often switch to windows. I often wanted wireless cards that work on linux without any effort. If you want a wireless card to work without any problem, buy a Prism chipset supported on linux exclusively at
http://prism54.org. The card that I have is a Netgear WG511 (Made in Taiwan and not China).

Yesterday I also got a Ralink chipset exclusively supported at http://rt2x00.serialmonkey.com/wiki/index.php?title=Main_Page for just $16.

My card is Gigabyte WMKG and it works flawlessly on linux. You can find other cards with Ralink chipset at http://ralink.rapla.net/

You may also find a huge bunch of Atheros chipset being supported at http://www.madwifi.org.

Backup your data periodically

REFERRED FROM : http://sushant354.blogspot.com/

Losing your computer data is a bad thing. One good habit is to regularly back up your data. But manually doing this is too cumbersome and so we need automated scripts to back up the data. Here is a small script that I use to back up my own desktop daily. It uses rsync protocol over ssh. You need to have ssh, rsync and ssh public-private key pairs for your back up machine. Setting up SSH key authentication is easy and here is one of the link http://www.ece.uci.edu/~chou/ssh-key.html

Add this script to your cron settings. For linux copy this file to /etc/cron.daily/ directory.

The benefit of using rsync is that only changes over the last week will be exported and it will save network bandwidth. SSH provides the encryption layer so that others cannot snoop on your data when you are backing up. This code is under Public Domain License. Customize it to your needs and auto back up your home directory from now onwards.

#!/usr/local/bin/bash

RSYNC=rsync
SSH=ssh
KEY=/home/sushant/.ssh/id_rsa
RUSER=sushant
RHOST=mybackupmachine.com
RPATH=backup/daily/`date +%u`
LPATH=/home/sushant/

$RSYNC -avxz --exclude=".*" --force --delete --delete-excluded --ignore-errors -e "$SSH -i $KEY" $LPATH $RUSER@$RHOST:$RPATH

TECH TIPS

In case of any problem in loading firefox extensions, delete the extensions.ini, extensions.rdf, extensions.cache files in the profile folder. They will be regenerated on firefox restart.
For eg: the profile folder will be /home1/rohithdv/.mozilla/firefox/e77hmcu6.default . where /home1/rohithdv is the home folder.