Transcript Linux ( ppt )

Welcome to Linux
Community
What is GNU/Linux?
A free Unix-type operating system developed
under the GNU General Public License.
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Open source
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Popular
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Support most of the platforms available
A Short History of UNIX
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Multics, AT&T Bell Lab, GE, MIT
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1969, UNIX, Ken Thompson, Dennis
Ritchie
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1973, Rewrite UNIX with C
Berkeley UNIX(BSD UNIX)
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Commercial products
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SunOS, Solaris, HP-UX, AIX, SCO UNIX
A Short History of Linux
A Short History of Linux(2)
Is Linux difficult ?
This may be true. But the real question is:
do you really want to learn it?
What are the benefits of Linux?
Linux can give you:
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A modern, very stable, multi-user, multitasking environment.
Advanced graphical user interface. Linux uses a standard, networktransparent X-windowing system with a "window manager" (typically
KDE or GNOME but several are available).
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The graphical desktop under Linux can be made to look like MS
Windows (or probably ANY other graphical user interface of your
choice).
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Dozens of excellent, free, general-interest desktop applications.
These include a range of web browsers, email programs, word
processors, spreadsheets, bitmap and vector graphics editing
programs, file managers, audio players, CD writers, some good
games, typing tutor, etc.
Freedom from viruses. Linux has no viruses because it is too
secure an operating system for the viruses to spread with any
degree of efficiency.
Linux is quite positively here-to-stay because of its open-source
nature (Linux cannot possibly be put out-of-business). It is a
standard selected for countless projects that are not going to go
away, and some of them are quite "mission-critical." Try the
International Space Station, for which Linux is the operating syste
(http://www2.linuxjournal.com/lj-issues/issue59/3024.html).
In a nutshell, the GNU General Public Licence (GPL) allows
anybody to:
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use the software at no charge, without any limitations,
copy, and distribute or sell unmodified copies of the software
in the source or binary form,
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use the software with propriatory (e.g., your own)
modifications, free of charge, as long as you do not distribute
or sell the modified version,
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modify, and distribute or sell a modified version of the
software as long as the source code is included and licenced
on the same terms as the original you received (the GPL),
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sell support for the software, without any limitations.
What the GPL license *does not* allow code recipients to do is to
take somebody elses software licenced under GPL, modify the
software, and then distrubute a this modified version of the softwar
under a propriatory licence. Speaking plainly, the GPL licence just
forbids stealing existing (somebody else's) software for incorporatio
into a closed, commercial-only product.
I need warranty and security. With
commercial software, I can sue if
things go wrong.
Things go wrong on many MS Windows NT machines every day,
and there are no damages awarded by courts. Read your MS
Windows license agreement to find out that there is no guarantee
whatsoever that ANYTHING will work. Trying to sue would be a
waste of your money.
Linux Distros
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A Linux distribution, often simply distribution
or distro, is a member of the Linux family of
Unix-like computer operating systems.
Distros mainly based on ‘Look and Feel’ and
Applications
：Distros:
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Red Hat Fedora, Debain, SuSe,Ubuntu,
Gentoo
File System
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Windows uses letters of the alphabet to
represent different devices and different hard
disk partitions. Under Windows, you need to
know what volume (C:, D:,...) a file resides on
to select it, the file's physical location is part
of it's name.
In Linux all directories are attached to the root
directory, which is identified by a forwardslash, "/". - root.
For example, below are some second-level
directories:
• /bin System binaries, including the command shell
• /boot Boot-up routines
• /dev Device files for all your peripherals
• /etc System configuration files
• /home User directories
• /lib Shared libraries and modules
• /lost+found Lost-cluster files, recovered from a disk-check
• /mnt Mounted file-systems
• /opt Optional software
•/proc Kernel-processes pseudo file-system
• /root Administrator’s home directory
• /sbin System administration binaries
•/usr User-oriented software
• /var Various other files: mail, spooling and logging
Linux Help
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man
info
command –help
Forums.
man command
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The “-k” option
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Manual pages are divided in 8 sections:
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User commands
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System calls
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Libc calls
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Devices
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File formats and protocols
Games
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man –k print
Conventions, macro packages and so
forth
System administation
To select correct section, add section number:
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man 1 passwd, man 5 passwd
info command
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A program for reading documentation,
sometimes a replacement for manual pages
Example : info ls
Links :
http://en.wikipedia.org/wiki/Unix
http://en.wikipedia.org/wiki/Linux
Download Source Code from:
http://www.kernel.org
Books:
Unix User Guide – Rebecca Thomas
Your UNIX: The Ultimate Guide-Sumitabha
Das
Thank you