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  Something you may not know about Shell

Shell is also called command line interface, it is the interface between *nix users and computer. Shell is a program which provides service to access OS kernel services. This article is to introduce some not so well known but useful and interesting knowledge about shell. Wiki shell was born almost at the same time as Unix. The first UNIX shell was written by Ken Thompson in 1971 and its name is Thompson sh. It's older than Linux kernel. The default Shell in most *nix and MacOS is bash, bash was...

   Linux, Unix,Shell,Command     2012-11-24 07:19:47

  I've run out of adjectives

The news of Dennis Ritchie's passing hit hard. So much has been written in the past day. His impact was enormous, and outside the tech world, mostly unknown - but very much felt. C underpins everything. My whole career has grown out of C and Unix. Wow.For most engineers working today, it's hard to understand the euphoria I felt in the 70s when a programming language finally came along that I (and everyone else) could use to move up from writing in assembler to a real programming l...

   Dennis Ritchie,James Gosling,Death,Praise,Comment,C     2011-10-20 02:55:58

  HeartBleed: OpenBSD now starts to clean up OpenSSL

Since the disclosure of HeartBleed bug in OpenSSL, some arguments emerge around the safety of OpenSSL, the largest open source SSL/TLS library used by large number of servers, applications. Some people are even starting to create their own version of SSL library. This includes OpenBSD, a famous Unix like open source operating system. Just a few days after the HeartBleed bug, OpenBSD forked a new branch of OpenSSL and started to clean up the forked branch and plans to merge it to its own cod...

   HeartBleed,OpenBSD     2014-04-15 04:21:26

  Ubuntu and GNOME jump the shark

I upgraded to Ubuntu 11.04 a week or so back in order to get a more recent version of SCons. 11.04 dropped me into the new “Unity” GNOME interface. There may be people in the world for whom Unity is a good idea, but none of them are me. The look is garish and ugly, and it takes twice as many clicks as it did before to get to an application through their supposedly “friendly” interface as it did in GNOME Classic. No, dammit, I do not want to text-search my applic...

   Ubuntu,GNOME,Open source,Unity     2011-10-17 11:19:00

  All Programmers Are Self-Taught

When I was a teenager I played high caliber baseball. I’m competitive to a fault and when I decide I want to be good at something, results usually follow. Now I’m a third year undergrad studying computer science. There’s something critically different between programming and sports though: A pitching coach teaches you how to pitch, but a CS professor doesn’t teach you how to code. I was surprised that neither my TAs nor professors critiqued my code during my firs...

   Programming,Style,Habit,Self learning     2011-12-21 10:25:50

  Networking Terminologies

Portmaps sudo apt-get install -y portmap Portmap is a part of ONC RPC (Open Network Computing Remote Procedure) collection of software for implementing remote procedure calls between Computer Programs. It is widely used by NFS (Network File System) and NIS. Portmap is a server that converts RPC program number to DARPA protocol port number. It must be used in order to make RPC calls. Network Infomation Service (NIS) sudo apt-get install -y nis NIS is a client server directory service provi...

   Linux,Network programming,Network file system     2012-02-16 06:22:30

  Do designers need code?

So many problems in software occur because programmers and designers don't communicate well all the time. Why don't more designers learn to code themselves or have engineers build abstractions better suited to them? People's minds work in different ways, they can process thoughts differently, solve problems in completely different but equally valid ways. It's a mistake to assume everyone should possess the same skill set.  Also not everyone should be a full stack engineer although full stac...

   Design,Coding     2014-01-07 06:22:52

  Smuggling data in pointers

While reading up on The ABA Problem I came across a fantastic hack.  The ABA problem, in a nutshell, results from the inability to atomically access both a pointer and a "marked" bit at the same time (read the wikipedia page).  One fun, but very hackish solution is to "smuggle" data in a pointer.  Example:#include "stdio.h"void * smuggle(void * ptr, int value){  return (void *)( (long long)ptr | (value & 3) );}int recoverData(void * ptr){  return (long long)ptr &...

   C,Pointer,Bit,Data,Atomic,Smuggle     2011-11-14 08:15:59

  System programming is still there

System programming is the practice of writing system software. System software lives at a low level, interfacing directly with the kernel and core system libraries. Your shell and your text editor, your compiler and your debugger, your core utilities and system daemons are all system software. But so are the network server, the web server, and the database. These components are entirely system software, primarily if not exclusively interfacing with the kernel and the C library. But nowadays more...

   System programming     2014-02-27 05:46:48

  Dates in PHP and MySQL

I see a lot of people on forums and on my training courses asking about the best way (or any way) to manage dates stored in a MySQL database and used in PHP. Three options follow, but first the problem.PHP uses unix timestamps for all its date functionality. It has methods to convert these timestamps into pretty much any text format you could want but internally it uses the timestamp format. A timestamp is simply an integer. Specifically, it’s the number of seconds that have ela...

   PHP,MySQL,Date format,Date,Comparison,Date compare     2011-10-17 14:00:57