Posts

Redox

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Redox is a Unix-like microkernel operating system written in the programming language Rust, a language with focus on safety and high performance.
Redox is inspired by previous kernels and operating systems, such as Minix or BSD.
The Redox OS Kernel is a hybrid kernel that supports X86_64 systems and provides Unix-like syscalls for primarily Rust applications.
The website can be found at https://www.redox-os.org.
After download iso file we can start Virtual Machine with Redox:




root / password




Have a fun ☺

REACTOS

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ReactOS

             is an operating system designed to be compatible with Microsoft Windows software.

We use iso file from http://downloads.sourceforge.net/reactos/ReactOS-0.4.3-iso.zip

After download we create virtual machine and start to install:














Now we can use ReactOS J

MikeOS

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this is first day of:http://www.qemu-advent-calendar.org/2016/ MikeOS
MikeOS is an operating system for x86 PCs, written in assembly language. It is a learning tool to show how simple 16-bit, real-mode OSes work, with well-commented code and extensive documentation. Features:
A text-mode dialog and menu-driven interface
Boots from a floppy disk, CD-ROM or USB key
Over 60 system calls for use by third-party programs
File manager, text editor, image viewer, games...
Includes a BASIC interpreter with 46 instructions
PC speaker sound and serial terminal connectionThe code is completely open source (under a BSD-like license), and is written by Mike Saunders and other developers.
Source: http://mikeos.sourceforge.net/


To run with VM Player:
- Download zip file from http://mikeos.sourceforge.net/#downloads
- Create new machine with option “Other”
After all we can use MikeOS  J






Rbash - way to restrict what users can do on your Linux systems.

Rbash - limited shell
If Bash is started with the name rbash, or the --restricted or -r option is supplied at invocation, the shell becomes restricted. A restricted shell is used to set up an environment more controlled than the standard shell. A restricted shell behaves identically to bash with the exception that the following are disallowed or not performed:

Changing directories with the cd builtin.Setting or unsetting the values of the SHELL, PATH, ENV, or BASH_ENV variables.Specifying command names containing slashes.Specifying a filename containing a slash as an argument to the . builtin command.Specifying a filename containing a slash as an argument to the -p option to the hash builtin command.Importing function definitions from the shell environment at startup.Parsing the value of SHELLOPTS from the shell environment at startup.Redirecting output using the ‘>’, ‘>|’, ‘<>’, ‘>&’, ‘&>’, and ‘>>’ redirection operators.Using the exec builtin to replac…

Quick UDP Internet Connections

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What is QUIC?

QUIC (Quick UDP Internet Connections) is a new transport protocol for the internet, developed by Google.






QUIC solves a number of transport-layer and application-layer problems experienced by modern web applications, while requiring little or no change from application writers. QUIC is very similar to TCP+TLS+HTTP2, but implemented on top of UDP. Having QUIC as a self-contained protocol allows innovations which aren’t possible with existing protocols as they are hampered by legacy clients and middleboxes.
Key advantages of QUIC over TCP+TLS+HTTP2 include: Connection establishment latency Improved congestion control Multiplexing without head-of-line blocking Forward error correction Connection migration

more / source:
http://blog.chromium.org/2015/04/a-quic-update-on-googles-experimental.html https://www.chromium.org/quic https://tools.ietf.org/pdf/draft-tsvwg-quic-protocol-02.pdf





Evolution of Unix and Unix-like systems

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The ‘Unix philosophy’ originated with Ken Thompson's early meditations on how to design a small but capable operating system with a clean service interface. It grew as the Unix culture learned things about how to get maximum leverage out of Thompson's design. It absorbed lessons from many sources along the way.

more / source:
http://www.faqs.org/docs/artu/index.html
https://en.wikipedia.org/wiki/Unix
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Directory contents -  Unix-like operating systems.



Directory structure and directory contents in Unix-like operating systems
- image from http://pclosmag.com/