SEARCH KEYWORD -- REFERENCE
How many bytes a boolean value takes in Java?
Have you ever wondered how many bytes a boolean value takes in Java? One byte, this might be the answer comes out of your mind right away. But is it? Let's dig in more. Per Oracle documentation on boolean value definition, there is below statement: boolean: The boolean data type has only two possible values: true and false. Use this data type for simple flags that track true/false conditions. This data type represents one bit of information, but its "size" isn't something that's precisely defin...
Books for entry level C programmers
In computing, C is a general-purpose programming language initially developed by Dennis Ritchie between 1969 and 1973 at Bell Labs Its design provides constructs that map efficiently to typical machine instructions, and therefore it found lasting use in applications that had formerly been coded in assembly language, most notably system software like the Unix computer operating system.To learn C, we need to read many C books and have many practices. Here we summarize a list of C books which may h...
/dev/null and /dev/tty in Linux
In Linux, there are two special files /dev/null and /dev/tty. /dev/null will drop all the data written to it, i.e, when program writes data to this file, it means the program has completed the data write operation. But in fact it does nothing, if you just want the status of a command but not the output of a command, this feature will be very useful. See below shell codes: /> vi test_dev_null.sh #!/bin/bash if grep...
Python internals: adding a new statement to Python
This article is an attempt to better understand how the front-end of Python works. Just reading documentation and source code may be a bit boring, so I’m taking a hands-on approach here: I’m going to add an until statement to Python. All the coding for this article was done against the cutting-edge Py3k branch in the Python Mercurial repository mirror. The until statement Some languages, like Ruby, have an until statement, which is the complement to while (until num == 0 is equi...
Python,New statement,Research,Addition 2012-03-12 07:32:24
Shortcut keys in Sublime Text 3(Animated demo)
Sublime Text 3 is a light weight code editor which supports lots of languages. It has lots of shortcuts and plugins easing work of programmers. In this post, we will introduce some shortcuts supported in Sublime Text 3 and show how powerful they are. 1. Select sibling matching(equal) word (Ctrl + D) Put the cursor on one word, press Ctrl + D to select the word, then press Ctrl and following by pressing D, it will select next matching word. The number of Ds pressed will mean number of matching wo...
TIPS,SHORTCUT KEY,SUBLIME TEXT 2016-04-28 02:41:28
Unix directory hierarchy history
As a beginner user of Unix or Linux, people would frequently get confused about the use of different directories of the system. For example, there is a /bin directory under root(/), it is used to store binary files. However, there are /usr/bin and /usr/local/bin under /usr which are used for storing binary files as well. Some systems even have /opt/bin. What are the differences among them? Though there are articles explaining different directories in *nix such as Filesystem Hierarchy Stan...
UNIX,LINUX,FILESSYTEM,DIRECTORY HIERARCHY,HISTORY 2016-10-21 23:47:17
Microsoft unveils a new logo
When releasing Windows 8, many people thought that Microsoft would use the blue logo as company's logo. But we are "cheated", Microsoft unveils a new logo. Watch video below. Since unveiling its first logo in 1977, Microsoft has changed its logo a few times, they are In 1977, its "Micro-Soft" Microsoft "blibbet" logo, filed August 26, 1982 at the USPTO and used until 1987. Microsoft "Pac-Man" logo, designed by Scott Baker and used from 1987 to 2012 with the 1994–2002 slogan"W...
How deep should unit test go?
There is a question on Stackoverflow which says "How deep are your unit tests?". It is asked by a guy named John Nolan. The question is not too new, but what catches me is the Best Answer given by Kent Beck, who is the creator of Extreme programming(XP) and Test Driven Development(TDD). Let's look at the question first. The thing I've found about TDD is that its takes time to get your tests set up and being naturally lazy I always want to write as little code as possible. The first thing I seem ...
How does GoLang know how many CPUs to use?
When running lscpu command on Linux, it will list the CPU info on the machine. Take one example where there is one CPU with 2 cores and each core has two threads which indicates there are 4 cores available. Now let's see how many cores GoLang program would identify. From output, NumCPU and GOMAXPROCS both output 4 which is expected. How does go runtime get this info, does it get it through similar command like lscpu or /proc/cpuinfo? Let's dig more in GoLang's source code. In runtim...
A trick of building multithreaded application on Solaris
Firstly, Let’s see a simple multithreaded application: #include <stdio.h> #include <pthread.h> #include <errno.h> void *thread1_func(void *p_arg) { errno = 0; sleep(3); errno = 1; printf("%s exit, errno is %d\n", (char*)p_arg, errno); } void *thread2_func(void *p_arg) { errno = 0; sleep(5); printf("%s exit, errno is %d\n", (char*)p_arg, errno); } int main(void) { pthread_t t1, t2; ...
RECENT
- Common Pitfalls When Handling JSON in Golang
- Streamlining the Project Invoicing Process: Tools and Strategies
- Performance comparison of string concatenation in Go language
- Why init() is not recommended in Go
- The Role of Coding Skills in Advancing Tech Careers
- Tips for Socializing With Friends During College
- Proximity Cards Do More Than Just Open Doors
- How to choose quality painted auto parts
- Oval engagement rings from MoonOcean: Elegance of form and individual approach
- Hologres vs AWS Redshift
- more>>