54 Geeky Tutorials in one spot

by Gina Trapani

It was a little more than a year ago that we decided to make Lifehacker into something more than just a link blog: a source of original feature articles on software and productivity that you won't find anywhere else. I chose the title "Geek to Live" for my twice-weekly feature post because it embodies what Lifehacker's all about: a tech-centric approach to solving common every day problems. (Oh yeah, and it's the site tagline, too.)

Right now you're reading the 100th installment of Geek to Live, which has spanned every one of my personal nerdy obsessions over the past year: from home networking, Firefox, and data security to personal finance, netiquette and web publishing. A lot happens in the course of a year, so today I've gone back and updated the dustier GTL installments and rounded up a giant look back at the series so far.

check it out: http://www.lifehacker.com/software/geek-to-live/geek-to-live-the-100th-installment-203491.php

Changing file permissions in UNIX or Linux

Command: chmod

This guide assumes that you already know a thing or two about UNIX and or Linux and basic computing.

1. The first thing you need to do is determine what permissions the file currently has assigned to it.
   e.g...
   $ ls -l
   total 4
   -rwxr-xr-x 2 owner group size date time filename
   $
   
   From this, you can determine that you are dealing with an ordinary file (-). The permissions are divided into 3 groups: Owner, Group, Other. So in this case the Owner has Read, Write and Execute permissions. The Group has Read and Execute and the Other has Read and Execute.
   
2. The next thing to do is determine what permissions you want the file to have. Let's say we want the Owner to have Read and Write permissions and Group and Other should only have Read permissions.
   
   That means we want it to look like this:
   -rw-r--r-- 2 owner group size date time filename
   
3. The command used to change permissions is "chmod". Here's some sample syntax:
   
   $ chmod a+rwx filename
   
   This means we want to add Read, Right and Execute permissions to "All" (All refers to Owner, Group and Other). a=all, g=group, u=owner, o=other, +=add permissions, -= remove permissions. Also for permissions r=read, w=write, x=execute. There are also many files types: -=ordinary, d=directory, p=pipe, etc. Here's another example...
   
   $ chmod g=rw filename
   
   This example removes Read and Write permissions on the file. Try some for yourself.
   
4. There is an easier way to do this. It involves converting the permissions to a binary format and then to a numeric format. To understand more about binary, check out wikipedia.org.
   
   Consider these permissions: -rwxr--r--
   Broken down: The first character is a (-) which indicates that it is an ordinary file. We will skip that part for now and focus on the remaining 9 characters (rwxr--r--). Now taking the remaining 9 charcters we can assume that if it has a number it gets a 1 and if it has a (-) then it gets a zero. This is how we translate the rwx values to binary:
   
   rwx r-- r-- (Break the characters up into three groups)
   111 100 100 (Assign a 1 or a 0)
   
5. So now you've got the binary values and need to translate that to numeric. So you simply replace the binary values with their numeric equivalents
   
   111 100 100
   7 4 4
   
6. Now the syntax works like this. You can assign the exact permissions for each type with one 3 digit numeric value. Let's say we want to assign rxw for Owner, r only for Group and r only for other. How can we do that only using numeric values?
   
   $ chmod 744 filename
   
7. And that's pretty much it. Try it yourself to see.

Binary Finger Counting

Install Hamachi 0.9.9.9-20 on Fedora Core 5: Part 1 of 2

If you are anything like me, then you are new to Linux and might be a bit lost. So I will be posting help as I learn new things. Here is an example of how to install Hamachi on FC5. This tutorial will teach you several things such as running commands from the terminal, uncompressing and unpacking files from the command prompt and how to download and install components for FC5 (in this case, GCC or GNU Compiler Collection).

Step one: Download Hamachi and save it to your home directory
Get it from here: http://www.hamachi.cc/download/

Step two: Uncompress and unpack the file

# tar -zxvf hamachi-0.9.9.9-20.tar.gz

Step three: Try to install it. CD to the unpacked hamachi directory and...

# make install

Step four: If you have no errors go to step 5. If you have an error saying that it won't install, then try the following. Install the GCC component.

# yum install gcc

Just answer 'yes' to any prompts that come up. Make sure you are connected to the internets. If you don't have the internets, then it should be available on the installation disc too.

Step five: After running a successful 'make install' then proceed,

# tuncfg

Step six: Then...

# hamachi-init

I'll post more details to this in Part 2 of 2. For now this should get you started.

Note: Hamachi ReadMe file located here: http://files.hamachi.cc/linux/README

Stephen Colbert has a bridge named after him

He did it. Stephen Colbert has had a bridge named after him.

From Wikipedia: http://en.wikipedia.org/wiki/Stephen_Colbert

On September 14, 2006, the Hungarian ambassador to the U.S. gave Colbert a Hungarian passport, Hungarian forint (equivalent to approximately $50 U.S.), and announced that a bridge in Hungary would likely be named after him. Stipulations presented by the Hungarian ambassador, however, included that Colbert must be fluent in Hungarian and must also be deceased.