Leap 42.1 is an under-development openSUSE flavour cooked from the SUSE Linux Enterprise (SLE) source code. If you haven’t heard already, this is not the only flavour for openSUSE going forward. Tumbleweed complements Leap. Tumbleweed is about bleeding edge while Leap is about stability. Continue reading Grab openSUSE Leap milestone 1
OS X Yosemite has introduced a Hypervisor framework to support user mode virtualization. xhyve is a lightweight virtualization tool that makes use of this to run Linux on OS X. The tool is a port of byhve (BSD Hypervisor) written as a KVM+QEMU alternative. Continue reading xhyve: Linux virtualization on OS X
LDT (Linux Driver Template) is a template for writing a new driver for the Linux kernel. While it is very useful for beginners, it can also work as a starting point for writing a new kernel driver. Continue reading LDT: Linux driver template for newbies
Veteran Linux kernel dev and maintainer Alan Cox announced a new System 5 Unix based kernel for those who want to start development with a bloat-free kernel. At the time of writing, the kernel needs just 40K memory (apart from userspace) to run.
Fuzix OS is great news for kernel enthusiasts considering the current status of the Linux kernel. Though it is a very powerful and popular kernel it has its own share of flak due to recent systemd controversies, a large number of contributors and a community reputed for using strong words.
Alan wanted a simpler system – both with respect to code and process. The driving factors had been a open source and free (including tools) CPU portable OS for Z80, support for unbanked memory configuration with basic features and compatibility.
Regarding platform support, Fuzix OS supports Zilog Z80 architecture right now. The code is straightforward and should be able to support other variants of the Z80 as well as T80 FPGA core. The code is built for 6809 and 6502 but an official platform support claim would need more testing. “In theory if it’s got 8bits and banked RAM you can probably run Fuzix OS on it”, Alan says.
The 8086 port is not available yet because a usable open source ANSI C for 8086 is not ready. Alan has done some initial work on Portable C Compiler (pcc) but he seeks help with it.
However, there are some drawbacks to this approach. First of all, the Z80 is a very old piece of hardware and not very commonplace. Developers would prefer opportunities around x86. In addition, pulling of a full-fledged kernel is not a very simple task so many of them available (in different stages of maturity) already.
On Github: Fuzix
XOS (eXperimental Operating System) is a instructional open source project for wannabe OS developers. The project aims to teach the techniques of writing a OS using a simulated machine termed XSM (eXperimental String Machine). The language for the core OS implementation is SPL (System Programmer’s Language) and application programs, which run on the OS, are programmed using APL (Application Programmer’s Language).
The steps to build the system (from checking out the development base to a shell) is chalked out in the ROADMAP. The task is to follow the steps and keep building the system. There are well defined specifications for the operating system, filesystem, XSM, SPL and APL.
The 4 software components needed for the development are:
- XSM Simulator
- XFS Interface
- SPL Compiler
- APL Compiler
All of these can be downloaded from the downloads page. Setup instructions are available in the ROADMAP. Development can be done on any Linux based operating system with GCC, Flex and Bison installed.
The government of the state of Tamil Nadu, India, led by Ms. Jayalalithaa has decided to go open source with BOSS (Bharat Operating System Solutions) Linux, an indigenously developed port of Linux by C-DAC (Centre for Development of Advanced Computing). It is a huge step for Linux, already a well known OS in India to get the official approval from one of the states of the largest democracy in the world. India being a major software hub, Linux has been around in India over a long time through software engineers and hackivists but the government offices by and large still depend on closed source software and Microsoft solutions. However, the Tamil Nadu government’s attitude towards Linux had always been different. BOSS Linux was the pre-loaded OS on the free laptops provided to students in the state around 2.5 years back. But moving to Linux at a government level is definitely a significant step. The state department of Tamil Nadu has considered the amount of savings that comes with the use of Linux and given its nod to the switch.
BOSS is a Debian derivative featuring the GNOME Desktop and supporting many Indian languages. It is free to download and use.
Regular Expressions which has always been vocal about governments moving to open source welcomes the decision of the TN government. Our readers might remember one of our past articles where we strongly advocated the use of open source solutions by governments not only for cost reduction but also for several other reasons.
Today IBM has released its own general purpose OS: FusedOS. As the name indicates, it is actually a fusion of a general purpose OS and a specialized OS the processes of which can talk to each other, unlike most OS -es which need to run on separate virtualized environments. Right now the prototype runs on the IBM Blue Gene/Q supercomputer (Linux runs on most of the supercomputers of the world, so this comes as no surprise) and combines a general purpose Linux kernel with the IBM compute node kernel (CNK). Both run from the same partition and applications for both the OS -es can be run on FusedOS. The applications can run simultaneously and can talk to each other as well. While you can run Linux processes over ssh, you need to invoke the cl tool for running CNK processes. Here’s a more detailed documentation on architecture and components of FusedOS.
IBM had long been a strong promoter of Linux. Good to see class innovations like this from IBM based on Linux. This also recognizes the growing visibility of Linux as a general purpose OS.
If you are accustomed to kill processes with kill(all),
<Ctrl-c> etc. on Linux you’ll be disappointed to know that there are some rare cases (or rather a process state) in which the process can’t be killed – the D+ state (D indicates “Disk sleep”). man ps says this is the uninterruptible sleep state. In layman’s terms the process is waiting for something (normally IO) and can’t do anything further, for example – die, till the IO operation is complete (no, this is not a deadlock where multiple processes wait on each other). It’s a kernel level sleep and a process is meant to be in this state for a fraction of a second. However, this sometimes lead to a process hang in cases like disk access or a buggy ioctl call. You can’t handle it even if you are the root (which is nothing but an enhanced privilege level to the kernel). The only way to get rid of it is a good old reboot.
Please note that this is different from the Z (zombie) state in which the process is simply waiting for the parent to read its exit status and can be killed.
Minix was written by Tanenbaum for teaching and Linus Torvalds adapted many of the design principles to write the Linux kernel. Minix still draws attention of budding operating system designers and programmers. The code for Minix 1.1 can be downloaded from any of the following links:
Here’s an interesting discussion on Linux initiated by Tanenbaum to which Linus replied back in his original inimitable style.