Usage Example
To list all of the spelling mistakes of the file “testfile.txt”, use:

aspell list < textfile.txt

To list all of the spelling mistakes of the HTML document “testpage.html”, use:

aspell --mode=html list < testpage.html

As always, be sure to take a look at the man pages for more information. Keep in mind that certain distributions may not come with aspell pre-installed, so you may need to use the package manager to install it (ie. apt-get install aspell or yum install aspell).

# /etc/bashrc

# System wide functions and aliases
# Environment stuff goes in /etc/profile

# It's NOT good idea to change this file unless you know what you
# are doing. Much better way is to create custom.sh shell script in
# /etc/profile.d/ to make custom changes to environment. This will
# prevent need for merging in future updates.

Here is a quick example for taking advantage of this hook which assigns a simple alias. First, you must setup /etc/profile.d/custom.sh:

/etc/profile.d/custom.sh
chmod +x /etc/profile.d/custom.sh

Second, you must created the contents of /etc/profile.d/custom.sh:

#!/bin/sh

alias ls='ls -lah'

Third, simply log out and then back in again. You’ll notice the changes. You can verify this particular example by using the alias command:

$ alias | tail -n1
alias ls='ls -lah'
$

Of course, you’ll want to take what you’ve learned above and run with your own script suited to your needs. I hope this has helped you achieve your goal of creating a universal profile for all users on the system.

1.) Open the terminal
2.) Copy/Paste the following into terminal

su -c 'rpm -Uvh http://download1.rpmfusion.org/free/fedora/rpmfusion-free-release-stable.noarch.rpm http://download1.rpmfusion.org/nonfree/fedora/rpmfusion-nonfree-release-stable.noarch.rpm'
su -c 'yum install -y rar unrar'

3.) Refer to the following pages for usage
Create/Compress/Archive Almost Any File in Linux (tar, tar.gz, tar.bz2, gz, bz, zip, 7z, rar, etc…)
Extract/Uncompress/Unarchive Almost Any File in Linux (tar, tar.gz, tar.bz2, gz, bz, zip, 7z, rar, etc…)

P.S.
For those die-hard one-liner fans out there, you can use the following instead:

su -c 'rpm -Uvh http://download1.rpmfusion.org/free/fedora/rpmfusion-free-release-stable.noarch.rpm http://download1.rpmfusion.org/nonfree/fedora/rpmfusion-nonfree-release-stable.noarch.rpm &&  yum install -y rar unrar'

As always, be sure to check out the man page for more information.

perldoc open

Reveals…

System::Library::Perl:User.Contributed PeSystem::Library::Perl::5.8.8::open(3)

NAME
       open − perl pragma to set default PerlIO layers for input and output

SYNOPSIS
           use open IN  => ":crlf", OUT => ":bytes";
           use open OUT => ’:utf8’;
           use open IO  => ":encoding(iso−8859−7)";

           use open IO  => ’:locale’;

           use open ’:utf8’;
           use open ’:locale’;
           use open ’:encoding(iso−8859−7)’;

           use open ’:std’;

DESCRIPTION
       Full‐fledged support for I/O layers is now implemented provided Perl is
       configured to use PerlIO as its IO system (which is now the default).
       ...
       ...

http://fungi.yuggoth.org/weather/
http://linuxshellaccount.blogspot.com/2008/09/bash-script-to-get-weather-forecasts.html

telnet rainmaker.wunderground.com

curl http://weather.noaa.gov/pub/data/forecasts/city/state/city.txt

tcpdump -i eth0 host 192.168.1.101

Now, run the ping test:

ping 192.168.1.100

At this point, if you get an output from tcpdump, you’ll know that the packet has made its way to the target machine (192.168.1.100). The next step would be to see if you ever received an acknowledgment from the target machine. Run arp on the machine doing the pinging (192.168.1.101):

arp -an

If you see something like ? (192.168.1.112) at (incomplete) on en1 [ethernet], that means you never got an acknowledgment back from the target machine (192.168.1.100).

At this point in this scenario, we would start to dive into what could be wrong. In this particular situation, it was a driver issue with assigning a MAC address to the interface.

This is just one scenario to get you familiar with how to use tcpdump and arp and gather information about the networking issue. Please refer to the utility man pages for more information.

I think it’s easy to get the idea based on the example above, but just in case you need inspiration, you could automatically remove these empty directories with the following (Careful! This uses ‘-rf’ flag which shows no warnings or mercy!):

find /path/to/directory -type d -empty -exec rm -rf {} \;

Check out some additional methods here:

http://www.cyberciti.biz/faq/linux-unix-shell-check-if-directory-empty/

tune2fs -i 0 /dev/<device node>

There’s more information here at this link for those of you interested:
http://serverfault.com/questions/28343/will-my-system-fsck-when-i-reboot

Minimize the receive latency of the serial device at the cost of greater CPU utilization. (Normally there is an average of 5-10ms latency before characters are handed off to the line discpline to minimize overhead.) This is off by default, but certain real-time applications may find this useful.