This subchapter looks at chmod, a UNIX (and Linux) command.
Teach Yourself UNIX/Linux System Administration and Shell Programming
table of contents
If you like the idea of this project,
then please donate some money.
more information on donating
This subchapter looks at chmod, a UNIX (and Linux) command.
chmod is used to change the permissions for a file or directory.
The chmod command was described in the first UNIX book, UNIX Programmer’s Manual, by Ken Thompson and Dennis Ritchie, published November 3, 1971.
The chmod 777 filename command will set the permissions so that filename is wide open to everyone.
$ chmod 777 filename
The file owner, the file owner’s group, and other (or world) will all be able to read, write, delete, modify, and execute (run) the file to their heart’s content. This access includes anyone who gets into your system through the internet.
On November 8, 2010, Ramesh Natarajan named this the number 32 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.
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).
return to table of contents
free downloadable college text book
free downloadable system administrator and shell programming book
Because I no longer have the computer and software to make PDFs, the book is available as an HTML file, which you can convert into a PDF.
Teach Yourself UNIX/Linux System Administration and Shell Programming
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
PO Box 1361
Tustin, California 92781
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)
Some or all of the material on this web page appears in the
free downloadable college text book on computer programming.
This web site handcrafted on Macintosh computers using Tom Bender’s Tex-Edit Plus and served using FreeBSD .
†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 11, 2012
Last Updated: September 28, 2012
return to table of contents
free downloadable college text book
free downloadable system administrator and shell programming book
