Today's Question:  What does your personal desk look like?        GIVE A SHOUT

SEARCH KEYWORD -- SHENZHOU SPACE STATION

  20 bit operations programmers should know

While talking about bit operation, programmers usually think about its efficiency. In embedded programming and system core optimization, appropriate use of bit operations is always a fascinating. When finding a job, it will help you a lot if you use bit operations when writing codes. Mastering simple bit arithmetic skills is necessary. 1. Get maximum int value int getMaxInt(){           return (1 << 31) - 1;//...

   Bit operation, Tips     2012-12-19 12:53:33

  CSS DIV position analysis

When using CSS to set the position of DIV, we may often get confused with the 4 position properties : static, relative, absolute and fixed. If we don't understand them correctly, we may often get unexpected result. Here we make some analysis to them.The definitions of these 4 properties:static : The default position property. It has no position actually. The element will appear where it should be (top, bottom, left, right or z-index has no use here)relative : This one will position relati...

   CSS, DIV,position,relative,absolute     2013-01-29 03:23:57

  Some useful Linux commands for teamwork

A small development team in the intranet will frequently transfer codes, share files. Here are some command we use frequently to release some of our work. They are not applicable to Windows users. 1. Output program execution output through GTalk. Sometimes we may need to send the program execution result and log to teammates for debugging using IM. These outputs are very troublesome to copy and send while in command line mode. So we could have a program called gpipe.py which can put GTalk as a p...

   Linux,NFS,GTalk,HTTP     2013-01-16 04:36:33

  Create Packed Indexes with MySQL

I am pretty much sure that you are aware of indexes which we are creating on database fields. Indexes are very useful to make your query search faster and improve the site performance. But the fact is that Indexes which we are creating on database tables also require some additional space on your hard disk and if you have not properly created these indexes than some t...

   MySQL,Compressed index,PACK_KEYS     2012-04-24 07:42:18

  How big is sizeof structure?

First let's see the codes of a structure: struct node{ int a; int b; }; Question : What's sizeof(node)? The answer is very simple, on a 32 bit machine, an int will take 4 bytes and two ints will take 8 bytes. So sizeof(node) is 8. The answer for the above codes is 8, then how about the following structure: struct node{ char a; int b; }; Question : Then what's sizeof(node) now? int takes 4 bytes, char takes 1 bytes, is the answer 5? Now the answer may not be 5, on some mac...

   Data structure alignment, pack     2012-10-29 12:13:37

  How to choose a jQuery plug-in?

jQuery plug-in provides a good way to save time and simplify the development, programmers don't need to write each component from scratch. However, the plug-in will also be a destabilizing factor in your code library. A plug-in saves countless development time, but a poor quality plug-in will cost more than the actual time to write your own component from scratch. Luckily, usually you have many pls to choose from, but even if you have only one plug-in, you also need to know whether it's worth us...

   jQuery, plug-in     2012-10-27 03:51:40

  Understand JavaScript prototype

For an front end programming language like JavaScript, if we want to understand its OOP feature, we need to understand its objects, prototype chain, execution context, closure and this keyword in deep. If you have a good understanding on these concepts, you should be confident that you can handle this language well. The inheritance in JavaScript is not class inheritance like Java, but it adopts another mechanism-- prototype inheritance. The key to prototype inheritance is the prototype chain mec...

   JavaScript, prototype, __proto__     2013-02-02 02:34:09

  Optimization Tricks used by the Lockless Memory Allocator

With the releasing of the Lockless Memory Allocator under the GPL version 3.0 license, we can now discuss more of the optimization tricks used inside it. Many of these are things you wouldn't want to use in normal code. However, when speed is the ultimate goal, sometimes we need to break a few rules and use code that is a little sneaky.The SlabA slab is a well-known technique for allocating fixed size objects. For a given object size, a chunk of memory is divided up into smaller regions of that ...

   Optimization,Memory allocation     2011-11-16 08:02:16

  About browser event

First look at following codes: var $ = KISSY.all; $(‘a’).on(‘click’,function(e){ doSomeThing();//This function seems very famous e.halt(); }); The above codes seem complete the work we want them. The browser will not redirect us to the link in href, but is there some issue with the codes above? Before explaining what's wrong with the above codes, we first need to understand some concepts. Browser default behavior When we click a link, the browser will redirect us to anoth...

   JavaScript event,Event bubbling,event capturing     2012-11-15 11:15:41

  IDC lists top 6 myths, realities about open source

Summary: What are the top 6 myths? That open source software will enter every market, is inherently innovative, it improves faster than commercial software, that it has less lock-in, that it’s free and that it has little benefit if one is not involved in the community. IDC calls these ideas “myths” but acknowledges there’s more than a grain of truth to all of them At its Directions 2012 conference in Boston today, IDC rev...

   IDC,Open source,Reality,Free,Contribution     2012-03-16 08:47:53

RECENT