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chown

summary

    This subchapter looks at chown, a UNIX (and Linux) command.

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chown

    This subchapter looks at chown, a UNIX (and Linux) command.

    chown is used to change the owner or group of a file.

    The chown command was described in the first UNIX book, UNIX Programmer’s Manual, by Ken Thompson and Dennis Ritchie, published November 3, 1971.

giving away a file

    You can use the chown to change the ownership of a file or directory, giving ownership away to someone else.

    The following example gives away ownership of the filename to the account newowner.

warning
Just read — do not type
this will give away your file and you have to use root to get it back

    $ chown newowner filename

    Of course, a system administrator can use root to freely change ownership of files and directories. This is a powerful tool in the hands of a system administrator.

security leak

    This command is often limited to only root (or superuser) because if a computer system or server enforces limits on how much disk storage space each account is allowed, someone can set a file so they still can read and write it (and possibly execute it, if applicable), then change ownership to anyone else. This gets the file (or entire directories) out of their storage limits, but they can still make use of the files.

other

    On November 8, 2010, Ramesh Natarajan named this the number 33 most frequently used UNIX/Linux command at this web page 50 Most Frequently Used UNIX / Linux Commands (With Examples).

    In June 2009, Ken Milberg named this command as one of the Top 50 universal UNIX commands at this web page Top 50 Universal INIX commands. Note that this web page requires agreeing to be spammed before you can read it.


free music player coding example

    Coding example: I am making heavily documented and explained open source code for a method to play music for free — almost any song, no subscription fees, no download costs, no advertisements, all completely legal. This is done by building a front-end to YouTube (which checks the copyright permissions for you).

    View music player in action: www.musicinpublic.com/.

    Create your own copy from the original source code/ (presented for learning programming).

    Work on this project is very slow because I am homeless. I am available for work if someone can provide an indoor place to work in Costa Mesa, California, electricity, internet connections, a flat raised working surface (such as a table or desk), a sitting device (such as a chair or stool), and a fully functional reasonably modern used computer. I’m already homeless, so you don’t need to pay me (and I understand how much business people hate the minimum wage law). Just give me a chance to work.


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free book on UNIX/Linux System Administration

Teach Yourself UNIX/Linux System Administration and Shell Programming

free computer programming text book project

Building a free downloadable text book on computer programming for university, college, community college, and high school classes in computer programming.

If you like the idea of this project,
then please donate some money.

send donations to:
Milo
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Tustin, California 92781

    At the time I am homeless. This greatly interferes with my ability to create this project, which can help nearly 20 million U.S. college students and more than 150 million students world-wide. I am looking for 30 rich people or corporations willing to donate $10 a month to my church so that the church can provide a place indoors for me to continue work. If you want to donate, please see help project. Thanks much.

Supporting the entire project:

    If you have a business or organization that can support the entire cost of this project, please contact Pr Ntr Kmt (my church)

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Some or all of the material on this web page appears in the
free downloadable college text book on computer programming.


I do the news as an unpaid volunteer for KOCI 101.5 FM, Newport Beach/Costa Mesa (also available on the web)


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Made with Macintosh

    This web site handcrafted on Macintosh computers using Tom Bender’s Tex-Edit Plus and served using FreeBSD .

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    †UNIX used as a generic term unless specifically used as a trademark (such as in the phrase “UNIX certified”). UNIX is a registered trademark in the United States and other countries, licensed exclusively through X/Open Company Ltd.

    Names and logos of various OSs are trademarks of their respective owners.

    Copyright © 2012 Milo

    Created: February 12, 2012

    Last Updated: September 28, 2012


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