A review of the characteristics of learning Linux _unix Linux

With its superior and stable network server performance, Linux has conquered many software and hardware manufacturers and the vast majority of computer fans. According to CNET, IDC data shows that Linux has taken second place in the server market. From 1998 to 1999,linux in the market share of the server has grown from 16% to 25%,IDC originally expected Linux will be in 2002 or 2003 years to become the market share second, unexpectedly this forecast 1999 will be achieved.
　　
Linux began as a hobby for Linus Torvalds of the University of Helsinki, Finland, when he wanted to build a Unix-like operating system that could be used on intel-based PCs instead of the Minix operating system. The logo (mascot) of Linux is a penguin. Since the release of LINUX1.0, it has become more and more popular with computer fans, and has been updated by the vast number of computer enthusiasts constantly supplemented.

Many parts of Linux are released under the protection of the GNU General Public License. This operating system is designed and implemented by hundreds of programmers around the world to create UNIX-compatible products that are freely available to the world without the copyright of any commercial software. By now, Linux is already a UNIX operating system used on personal computers and workstations, a free version of UNIX, and its basic system is very low on hardware and is fairly stable on many systems.

Linux is the only operating system available for free, multitasking, multi-process functionality for PCs and multiple users. A free software that can be freely obtained from the Internet or other channels. Installing Linux can not only experience the taste of being a system administrator, but also provide a cheap opportunity for the authors to understand the world's popular Unix operating system, and create their own web sites by opening up some services on the web. Today's popular versions are: Turbo Linux, RedHat Linux, Slackware Linux, Solaris. China is supported by Red Flag Linux.

The author contacts Linux later, has spent a period of time to learn Linux, will study notes sorted as follows, hope to work with Linux masters, enthusiasts learn from each other.

Overview of Linux Features

First, the system characteristics

Linux system has a text editing interface and graphical user interface (GUI), the author prefers to GUI interface simulation terminal for command input. Its features include: Multi-User, multi-task, multi-platform, programmable shell, provide source code, simulation terminal, support a variety of file systems and powerful network functions.

Multiuser: Multiple users (six) can simultaneously work with a copy of the same application from the same or different terminals (terminal number: TTY1~TTY6). In the console, the Switch Terminal command is: ALT+F1~F6; in the Emulation terminal window (ps/0~n) is: Shift+alt+f1~f6.

Multitasking: Multiple programs can be executed at the same time, without any hindrance between programs. With Windows? Differently, Linux uses all the remaining physical memory that the system does not use to make the hard disk cache. The author once opened three xterm, used to find files, debug programs, email. You can also specify that a program runs in the background and that some programs run at a specific time (at command).

Multi-platform: Linux can be run on the X86 platform and can be ported to other platforms.

Programmable Shell:shell is the system shell that interprets and executes commands. The system is more personalized by writing shell programs, and it has the function of C language in some programs.

Provide source code: Linux is free software, the source code is completely open, you can compile the kernel, modify and expand the operating system, two times development.

Linux supports a number of file systems, such as EXT2, NFS, VFS, ISO9660, Msdos, and so on.

Network functions: A more comprehensive implementation of TCP/IP, SLIP, PPP, Plip protocol, powerful.
　　
Second, system comparison

Linux can coexist with other operating systems on the PC, but there are differences.

(i) Linux and Msdos

Dos in the PC on the widest popularity, low prices. Linux is free software, regardless of price. Some Linux commands are the same as or similar to M s-dos, such as CP----copy, CD (..) ---cd (..), telnet---telnet, etc. to be in Linux under the DOS command, to add m;linux before the command can also give full play to the function of the microprocessor, its multi-user, multitasking, network functions such as MSDOS can not be compared. It is common for LI N U X and DOS to be installed on the same machine.
　　
(ii) Linux and Windows

Both are multitasking operating systems that support the same user interface, network, and security. However, Windows is a dedicated system, developed by the company to control interfaces and designs, and establishes stringent standards, and buys high prices. And Linux is free software, its development using open and collaborative mode, thus conducive to the full process of the collective wisdom of personnel, a large number of unnecessary duplication of work, and make free software weaknesses can be found in time and overcome, has a strong vitality. Linux is competing for UNIX and Windows NT market share. It is the only operating system that can contend with Microsoft Windows, and Gates admits that Linux is Microsoft's competitor.

(iii) Linux and UNIX

In essence, Linux is a version of UNIX. UNIX supports more hardware, and Linux-supported hardware is growing. It is striking that Linux is at least as stable as commercial UNIX. For many users, the most important factor is the price; obviously Linux has an advantage at this point. Linux enables users to run full Unix on a PC. So Linux provides a cheap opportunity for the authors to learn about UNIX.
　　
Third, shortcomings:

The biggest disadvantage of using Linux is that no entity is responsible for its development. Linux developers are scattered around the world, they can publish their own programs, no formal quality assurance procedures.

1, because of the development of decentralized, Linux lack of technical support, the author often encountered many problems, do not know how to solve, look up the data and can not find----This is the author of the main reasons for many installations;

2, and can not install and run on all hardware platforms. The hardware that Linux supports depends on the hardware that each developer uses to write the code.

3, some application software, especially for WINDOWS, DOS, can not be used on Linux. The solution now is to coexist with other operating systems on a single machine.

4, in addition, the author feels that the installation software is not smart enough, sometimes need to recompile the kernel, but also to modify makefile files, time-consuming and laborious, but also often installed----may not be optimized, configured a good kernel.