Ever wonder what the CEO of one of the world’s leading music retailers thinks of Digital Rights Management? Today Steve Jobs of Apple Inc. told us in a message titled “Thoughts on Music” which I hope we will some day look back on as the beginning of the end for DRM.

In the post Jobs clearly presents the current situation (each vendor has their own library of music, protected by their own DRM which will only work on their own software and devices) and offers up three possible futures, the most interesting of which is the third:

The third alternative is to abolish DRMs entirely. Imagine a world where every online store sells DRM-free music encoded in open licensable formats. In such a world, any player can play music purchased from any store, and any store can sell music which is playable on all players. This is clearly the best alternative for consumers, and Apple would embrace it in a heartbeat. If the big four music companies would license Apple their music without the requirement that it be protected with a DRM, we would switch to selling only DRM-free music on our iTunes store. Every iPod ever made will play this DRM-free music.

Why would the big four music companies agree to let Apple and others distribute their music without using DRM systems to protect it? The simplest answer is because DRMs haven’t worked, and may never work, to halt music piracy.

If you are interested in DRM or would like to learn more about it and why it’s such a hot topic right now, I highly recommend reading Jobs’ entire post. Remember, Apple is currently ahead in this field and if anything has the most to loose if they lost their brand lock-in.

drm, digital rights management, music, mp3, aac, apple, computer, records

Nobody will argue that testing your code is an essential, but often neglected step to good development. Effective testing not of the whole application, but portions of it is the focus of the Oracle Development Tools User Group PL/SQL Test-A-Thon to be held Febuary, 28-March, 1 of this year in California.

Here’s how the challenge works:
After the end of sessions on the first day, you will be presented with four programs that perform typical operations—nothing exotic. Along with those programs come supporting test data, a list of tests that you need to perform, and the results you should get for each test (most will be successful, but some will fail). You will then have one hour to write a test to show which tests succeed and which fail for the programs. Your test results should be self-verifying. That is, we will not manually verify your tests to see if they worked or not.

Check out more about the contest and about the Oracle Development Tools User Group conference. While not overly active the Oracle Development Tools User Group site has some interesting content as well.

sql, plsql, oracle, development, software development, database, dba

Thanks to YouTube you now have no excuse for missing the commercials that everyone will be talking about next week.

Picking up the slack left behind from when AdCritic went pay, YouTube already has their Super Bowl Commercial page ready to go.

Super Bowl Commercials

So, whether you want a second viewing of the commercials (some of which may never be shown again) or you just think that a four hour (or more) football game is too much to sit through for a few minutes of cool ads, YouTube has you covered

commercials, funny commercials, funny, fun, football, youtube, video, super bowl

Never Forget!As this was all going down yesterday I thought it a bit of an overreaction that the Massachusetts bomb squad was being dragged out for what was obviously an LED array (even from what little video the news stations had.) Now Sean Stevens and Peter Berdovsky who placed the devices around the city are being charged with placing “hoax devices” and disorderly conduct.

Now lets, just for a moment, review the definition of the word “hoax“. Now, if you read it carefully you’ll notice it starts off “to trick…” The phrase “to trick”, at least to me, implies intent. If you’re paying any attention to the reasons these guys (and folks like them in other US cities) put the devices up and what their purpose was you know already that there was no “trick”.

But anyway, while the press is busy sensationalizing the whole incident, the two men are taking time to learn a bit about hair styles of the ’70s! Really! Click through and watch the video. Bravo to these guys for not feeding the media machine!

Get these guys for graffiti, maybe even trespassing; even disorderly conduct, but they’re not terrorists. Now, Turner Broadcasting and the ad agency they hired that came up with the idea have a bit more to answer for, although the campaign was received quite differently in other cities. If they had any brains at all they’d have walked into Boston today with an apology and a million dollar check.

The MAKE blog (where I stole the image from, hope they don’t mind) continues to have some interesting information on the event.

publicity, graffiti, prank, led, technology, cool

Linux file security is quite simplistic in design, yet quite effective in controlling access to files and directories.

Directories and the files which are stored in them are arranged in a hierarchical tree structure. Access can be controlled for both the files and the directories allowing a very flexible level of access.

File Security Model

In Linux, every file and every directory are owned by a single user on that system. Each file and directory also has a security group associated with it that has access rights to the file or directory. If a user is not the directory or file owner nor assigned to the security group for the file, that user is classified as other and may still have certain rights to access the file.

Each of the three file access categories, owner, group, and other, has a set of three access permissions associated with it. The access permissions are read, write, and execute.

A user may belong to more than one group. Regardless of how many groups a user belongs to if permissions are granted on a file or directory to one of the user’s groups they will have the granted level of access. You can check what groups a user belongs to with the groups command.

$ groups tclark
tclark : authors users

The groups command is called with one argument, the username you want to investigate. As you can see in the output above the output lists the username and all the groups they belong to. In this output tclark belongs to the groups authors and users.

From the information previously presented about file and directory commands, using the –l option with the ls command will display the file and directory permissions as well as the owner and group as demonstrated below:

Viewing permissions, owner and group

The ls –l command is the best way to view file and directory ownership and permissions. Now let’s look at what each of these permissions do.

File Permissions

File permissions are represented by positions two through ten of the ls –l display. The nine character positions consist of three groups of three characters. Each three character group indicates read (r), write (w), and execute (x) permissions.

The three groups indicate permissions for the owner, group, and other users respectively.

Breakdown of the permissions listing

In the example above, both the owner and the group have read (r) and write (w) permissions for the file, while other users have only read (r) permission.

The example below indicates read, write, and execute (rwx) permissions for the owner, read and execute (r-x) permissions for the group, and no permissions for other users (—).

Another permission listing breakdown

The alphabetic permission indicators are commonly assigned numeric values according to the scheme shown in the table below:

Alpha Numeric Permission
0 No permission granted
x 1 Execute permission granted
w 2 Write permission granted
r 4 Read permission granted

Then, each three character permission group can be assigned a number from zero to seven calculated by adding together the three individual numeric permissions granted. For example, if the owner has read, write, and execute permissions, the owner’s permissions can be represented by the single digit 7 (4+2+1). If the group has read and execute permissions, that can be represented by the single digit 5 (4+0+1). If other users have no permissions, that can be represented by the single digit 0 (0+0+0). These three numbers would then be listed in the order of owner, group, other, in this case 750 as a way to definitively describe the permissions on this file.

There are some additional abbreviations that can be used with commands that manipulate permissions. These abbreviations are:

  • u: user owner’s permissions
  • g: group’s permissions
  • o: other’s permissions

These abbreviations can also be used to change permissions on files. As we will see later, they will allow you to manipulate one level of the permissions (perhaps just the permissions granted to group) without changing the others.

Of course just being able to read these permissions isn’t enough… we want to be able to manipulate them. Stay tuned for more on that in the near future.

Easy Linux CommandsFor more tips like this check out my book Easy Linux Commands, only $19.95 from Rampant TechPress.

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unix, linux, system administration, sysadmin, hidden files, config files

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