Linux exercises 01

1. What is the relationship between Unix and Linux?

Answer: 1) origin

UNIX originates more than Linux, Linux is a Unix-like product, Linux products mimic UNIX systems and functions, and are a set of operating systems compatible with System V and BSD Unix.

2) Business

UNIX is a commercial software that implements intellectual property protection for source code, and Linux is free software that develops source code.

3) Use

(1) Commercial UNIX supports a little more hardware, mostly with hardware, and Linux can run on a variety of hardware platforms.

2. What is BSD? What do we usually say about FreeBSD, NetBSD, and BSD?

A: BSD (Berkeley software distribution, Berkeley Software suite) is a UNIX derivative system that was developed and released by UC Berkeley in the past 1977-1995 years.

Freebsd

FreeBSD was developed on the basis of 386BSD, and 386BSD was a BSD version of the Intel 80386 chip developed by the Berkeley computer scientist Bill Jolitz. For this reason, FreeBSD always works best on a 32-bit system x86 machine. In the free BSD, it works best with PC compatible machines, and the number of supported PC-compatible external devices is also the most. Although FreeBSD can also run on the Alpha processor, porting to other architectures is in progress, but you should consider it a major operating system for the x86 system.

NetBSD
NetBSD is also a free BSD, it is based on BSD's most portable operating system. Currently capable of running over 46 different hardware architectures (they are working to make it adaptable to more architectures), NetBSD works well from the original 68K-based Macintosh or Amiga to the X86-64 hammer structure that AMD has not yet published.

3. UNIX licenses prohibit the use of UNIX source code in universities which year, followed by the emergence of two important UNIX version of the line, what is the difference?

A: Unix version V7 began in 1979, and UNIX licenses began to prohibit the use of UNIX source code in universities, including in the course of teaching.

There are two major UNIX version lines, one is Berkeley BSD and the other is UNIX at/T.

4. AIX, Solaris, HP-UX, IRIX which companies have these UNIX developed? Which branch of Unix derivation are they based on (the two version lines in question 3rd)?

A: AIX was developed by IBM and is based on the Unix System v at/t;

Solaris was developed by Sun Microsystems Corporation, based on BSD Unix-derived;

HP-UX is developed by Hewlett-Packard Corporation and is based on Unix System v;

IRIX is developed by the Silicon Valley graphics company, based on BSD and System V Unix-derived;
5. Please explain the concepts of GNU and GPL in the shortest words.

A: GNU: is a completely free operating system that is free to use, copy, modify, and publish.

GPL:GPL is the GNU General Public License, the "anti-copyright" (or copyleft) concept
6. What are the changes in GPLv2 and GPLV1?

A: The biggest change in GPLv2 is the addition of "freedom or Death" ("Liberty or Death"), the seventh chapter Liberty-or-death Presentation. This chapter states that if a person releases software from the GPL, it also adds mandatory terms to protect and respect some other people's freedom and interests to a certain extent (i.e., in some countries, people can only release software in the form of binary code to protect the copyright of developers who develop software). Then he will have no right to publish the software.

Answer:

1. What is the relationship between Unix and Linux?
Linux is a Unix-like system, and it can be said that Linux is derived from UNIX systems.

2. What is BSD? What do we usually say about FreeBSD, NetBSD, and BSD?
BSD is an important UNIX branch, developed and released by the University of California, Berkeley, in the last 1977-1995 years. Both FreeBSD and NetBSD are a derivative version of BSD.

3. UNIX licenses prohibit the use of UNIX source code in universities which year, followed by the emergence of two important UNIX version of the line, what is the difference?
Unix's version V7 started in 1979, and it banned UNIX sources at universities. Then there are two major UNIX version lines, one is Berkeley's BSD Unix and the other is the Unix System v family.

4. AIX, Solaris, HP-UX, IRIX which companies have these UNIX developed? Which branch of Unix derivation are they based on (the two version lines in question 3rd)?
AIX is developed by IBM and belongs to the System V branch;
Solaris was developed by Sun Microsystems and developed from BSD, preferring system V;
HP-UX developed by Hewlett-Packard, based on System V branch;
Irix is a Silicon Valley graphic company developed based on the System V branch;

5. Please explain the concepts of GNU and GPL in the shortest words.
GNU is a free software campaign launched by Richard Stallman in 1983 to create a completely free operating system that requires us to be free to use, freely change, free to release software, and the GPL is used to prescribe how to free the protocol.

6. What are the changes in GPLv2 and GPLV1?
GPLv1 was released in 1989, and its main purpose was to prevent such behavior: the author of the release software publishes only the binary executable, not the source code, and the author of the software adds some restrictive clauses. Therefore, by GPLV1, if you publish executable binaries, you must publish the readable source code at the same time, and you cannot add any restrictive terms when publishing any GPL-based software. The biggest difference between GPLv2 and GPLV1 is that there is a chapter in the second edition of the clause "Freedom or Death" ("Liberty or Death"), which affirms that if a person publishes GPL-based software, it also adds mandatory terms, In order to protect and respect other people's freedom and rights to some extent, that is, in some countries, people can only release the software in the form of binary code, in order to safeguard the copyright of developers, then he will not be entitled to publish the Software.

Linux exercises 01