Linux Kernel - Intro

I see it important to give a bit of information regarding the Linux kernel , for whom don't know more than that Linux is power fulled cause of kernel without knowing anything more about it.

We can say that the __Kernel__ is the core of operating system;
it is the program that controls the basic services that are utilized by user programs.

The kernel is responsible for:
-CPU resource scheduling (regarding process management)
-Memory management (including protection implementation)
-Device control (providing the device-file/device-driver interface)
-Security (device, process and user level)
-Accounting services (including CPU usage and disk quotas)
-Inter Process Communication (shared memory, semaphores and message passing)

Kernel does the memory management for all of the running programs (processes) and that they all get a fair share of the processor’s cycles, also provide portable interface for programs to talk to hardware.

It is physically a file that is usually located in the /boot directory. Under Linux, this file is called vmlinuz.

Foo-bar:/home/mina# ls -l /boot/vm*
-rw-r--r-- 1 root root 1231478 Jan 24 2005 /boot/vmlinuz-2.6.8-2-686-smp

-The size of the kernel is Dependant on what features compiled into it, what modifications made to its data structures and what additions made to its code.

-vmlinuz is referred to as the kernel image. At a physical level, this file consists of a small section of machine code followed by a compressed block. At boot time, the program at the start of the kernel is loaded into memory at which point it uncompresses the rest of the kernel.

-/usr/src/linux is a soft link to /usr/src/ within this directory hierarchy are in excess of 1300 files and directories which consists of around 400 C source code files, 370 C header files, 40 Assembler source files and 46 Makefiles. These, when compiled, produce around 300 object files and libraries; large portion of this is driver code.

-Only drivers that are needed on the system are compiled into the kernel, the rest can be placed separately in things called modules.

-Kernel Boot steps:

1) The boot loader program (e.g. grub) starts by loading the vmlinuz from disk into memory, then starts the code executing.
2) After the kernel image is decompressed, the actual kernel is started. This part of the code was produced from assembler source.
Technically at this point the kernel is running. This is the first process (0) and is called swapper. Swapper does some low level checks on the processor, memory and FPU availability, then places the system into protected mode. Paging is enabled.
3) Interrupts are disabled though the interrupt table is set up for later use. The entire kernel is realigned in memory (post paging) and some of the basic memory management structures are created.
4) At this point, a function called start_kernel is called.
start_kernel is physically located in /usr/src/linux-2.x.x../init/main.c and is really the core kernel function.
5) start_kernel sets up the memory, interrupts and scheduling.
In effect, the kernel now has multi-tasking enabled.
The console already has several messages displayed to it.
6) The kernel command line options are parsed (those passed in by the boot loader) and all device driver modules are initialized.
7) Then memory initializations occur, socket/networking is started and bug checking.
8) The final action performed by swapper is the first process creation with fork whereby the init program is launched. Swapper now enters an infinite idle loop.

-The timer interrupts are now set so that the scheduler can step in and pre-empt the running process. However, sections of the kernel will be periodically executed by other processes.

Comment or give some detailed discussion if you do like.

The ! bit bucket five things to know when you switch to Linux:

#1: App-searching is a pleasure, or: How to install and uninstall programs
#2: Be wary when going root, or: The command-line and the root user
#3: Two (different) sides to a coin, or: GNOME and KDE
#4: You-may you-may-not, or: File permissions
#5: Five more quick tips, or: Various additional details

-No defragmenting needed( file systems in use are extremely resistant to fragmentation )
-Anti-viruses made redundant
-Case-sensitive filenames
-Hidden files start with a dot
-Accounting for hardware (i386)

Linux Kernel 2.6.8.1

Linux Kernel 2.6.8.1

Flowchart for all those who say linux-kernel is complicated. :) :)
i guess they'll know what complications are :D .
by , Oregon State Univ. LUG

Linux XP

21/9/2006 Linux XP Desktop is officially released. Linux XP Desktop is a full-featured PC operating system like Windows™ (same Look and feel) but based on Fedora, the stable and secure Linux platform.

Linux XP Desktop comes with a complete software bundle including

• OpenOffice suite,
• planning, project management,
• e-mail, calendar/todo,
• Internet, ICQ/MSN/etc,
• audio/video conferencing,
• file sharing and exchange,
• raster and vector image editors,
• movie and music players,
• internet radio, TV, dictionaries,
• software development tools.
• More .....

For more Information

• Linux XP Desktop website
• Key Features
• Screen Shoots
• Download Mirrors

IEs 4 Linux

What is IEs4Linux?
IEs4Linux is the simpler way to have Microsoft Internet Explorer running on Linux.
No clicks needed. No boring setup processes. No Wine complications. Just one easy script and you'll get three IE versions to test your Sites. And it's free and open source.
By the way, you can be on FreeBSD or Solaris too, instead of Linux.

How can I get this wonderful software?

First, get Wine and cabextract. (need help with this? click here)
Now, Download IEs4Linux. Extract it. Open a terminal. Run the 'ies4linux' executable. That is it.

FreeDos

FreeDOS aims to be a complete, free, 100% MS-DOS compatible operating system (mostly achieved.) Today, FreeDOS is ideal for anyone who wants to bundle a version of DOS without having to pay a royalty for use of DOS. FreeDOS will also work on old hardware, in DOS emulators, and in embedded systems. FreeDOS is also an invaluable resource for people who would like to develop their own operating system. While there are many free operating systems out there, no other free DOS-compatible operating system exists. About

Microkernel Debate :

micro vs monolithic kernel, do you share the address space with the
caller or put in slightly different terms: can the callee look at and change
the callers state as if it were its own .

Scponly

what is scponly?:

scponly is an alternative 'shell' (of sorts) for system administrators
who would like to provide access to remote users to both read and
write local files without providing any remote execution priviledges
it is best described as a wrapper to the tried and true ssh suite of
applications.