Linux with Operating System Concepts

packagename
. As 
an alternative, you can also use the option 
erase
. There is also a 
groupremove
, which 
removes all packages of the same group.
Whichever approach is taken to remove the software package, make sure that your users 
know of its removal. They might have a shock if their favorite piece of software suddenly is 
missing! Additionally, if there are any symbolic links pointing at the software, these should 
all be removed.
13.8 THE OPEN SOURCE MOVEMENT
The simplicity of yum (or apt-get) seems to make rpm and make/make install obsolete. 
In fact, the former is generally true but the latter is not the case. Why would you want to 
download source code only to have to compile it prior to installation? This added step can be 
time consuming and also involve effort on your part if the makefile requires modification.
On the other hand, one of the greatest strengths of Linux is that so much of its software 
is available in source code. In this section, we explore the open source movement and the 
open source community. Why does it exist? Why do people contribute? What does it mean 
to you as a system administrator?
13.8.1 Evolution of Open Source
The open source movement can be traced back to perhaps two groups of programmers. 
There was Richard Stallman at MIT’s artificial intelligence laboratory who created the 
GNUs project. GNU stands for GNU Not Unix, a recursive definition (recursion is a pro-
gramming tool commonly used in artificial intelligence). What Stallman had in mind was 
the creation of a Unix-like operating system and its application software. GNU would be 
offered entirely as source code, free of charge but also free to be modified by whomever 
desired to work on it. Programmers could modify, enhance, or alter the code as they saw 
fit. Whatever they produced would then be made available in source code format.
The second group of programmers was centered at the University of California at 
Berkeley, who were working on their own dialect of Unix, fronted by one of the original 
Unix creators. This version of Unix became known as the Berkeley Standard Distribution, 

---

Software Installation and Maintenance
◾
563
or BSD Unix. While funded by the government to create this version of Unix, they also 
called up other Unix developers to assist for free. They also had the intention of freely dis-
tributing BSD Unix.
Both groups worked on their respective operating systems starting in the late 1970s, 
working through the 1980s. While GNU Unix was never completed in the sense that a 
formal release has not been distributed, BSD Unix became very popular. At this time, no 
one was referring to this ideology as open source. But in the mid-1980s, Richard Stallman 
created the free software movement. His specific definition of free software was that it was 
“free as in free speech,” not “free as in beer.” He opposed proprietary software and saw the 
software field as one where all programmers could or should contribute to the development 
of software. Software, he felt, were based on ideas and ideas could not be owned. Therefore, 
proprietary software was immoral.
Stallman created the GNU General Public License (GNU GPL). The GPL requires that 
software published under the GPL must be free for anyone to use for any purpose, free to be 
studied, free to be changed, free to be redistributed, and free to be improved. The proviso 
is that anything created by GPL software would also be published under the GPL so that 
further distribution of such software would also be available as source code allowing oth-
ers the same freedoms.
In 1991, Linux Torvalds created Linux and freely distributed the source code to other 
programmers who might be willing and able to contribute. Again, the notion is that the 
community as a whole can contribute to and improve the operating system.
Open source was further enhanced when the creators of the Netscape web browser fol-
lowed this ideology. In fact, it was the Netscape group that coined the term open source 
and the open source initiative.
With the inclusion of Linux and Netscape, the free software movement fell into dis-
pute. Torvalds did not require that modified versions of software be made freely available. 
Instead, he felt that if a person modified a piece of open source code, the modified code 
could continue to be freely distributed as source code, or it could be freely distributed but 
as executable code, or it could even be sold for profit. This created a rift between various 
open source contributors.
On the one hand, contributors felt that any use of open source software should result 
in open source products. That is, someone who is modifying or otherwise contributing 
to open source software would be required to contribute their products back to the open 
source community. Others felt that some contributions could be marketed commercially 
or otherwise have restrictive licenses applied to the products.
The rift caused the community to splinter into two groups: the Open Source Initiative 
(OSI) and the Free Software Foundation (FSF). The difference being that the OSI is willing 
to accept copyrights on some software that restrict the freedoms over the GPL while the 
FSF generally feels that anything created from a GPL produced product must also be made 
available in open source under the GPL.
Today, we find roughly 50% of Red Hat Linux code (both the operating system and 
applications software) is published under the GPL. This means that half of Red Hat is 
freely available for use and modification and half is at least somewhat protected by a more 

---

564
◾
Linux with Operating System Concepts
restrictive copyright. Some of this latter group of software is available for free but with 
distribution restrictions or available for free but not in source code format, and some is not 
free. Table 13.4 provides a list of notable software published under the GPL.
It should be noted that Stallman has referred to the GPL as a 
copyleft
, not a copyright. 
The copyleft is not the antithesis of a copyright as the copyleft is still a legal mechanism that 
requires that software enhanced or modified from GPL software be published under the 
GPL copyleft (for details on the GPL, visit the GPL website at http://www.gnu.org/copyleft/
gpl.html). The opposite of a copyright presumably would be public domain, which means 
there are no laws at all governing its usage.
Today, we find many outside of the Linux community embracing the open source ini-
tiative and using the GPL or a similar mechanism. There are many software developers 
contributing to open source. These include, for instance, employees at Microsoft who are 
now producing some software for free in source code format. Thus, Microsoft has become a 
partner in the development of some open source software. In fact, there are many ongoing 
open source projects at Microsoft, including those that impact Apache, the dot net (.net) 
languages and platform, Silverlight, and SQL database tools to name a few. A summary of 
Microsoft’s involvement can be found at http://www.microsoft.com/opensource/directory.
aspx. Today, we find open source contributions impacting all of the operating system plat-
forms: Windows, Mac OS, Linux, and Unix.
This shift in perspective not only has impacted software developers’ perspective of 
open source but companies as well. Early on, open source software was primarily used 
TABLE 13.4 
Popular Open Source Software Titles