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

SEARCH KEYWORD -- NULL safe

  The Evolution of a Programmer

High School/Jr.High 10 PRINT "HELLO WORLD" 20 END First year in College program Hello(input, output) begin writeln('Hello World') end. Senior year in College (defun hello (print (cons 'Hello (list 'World)))) New professional #include <stdio.h> void main(void) { char *message[] = {"Hello ", "World"}; int i; for(i = 0; i < 2; ++i) printf("%s", message[i]); printf("\n"); } Seasoned professional #include <iostream....

   Humour,Evolution,Programmer     2012-04-23 06:30:33

  Use DTrace to diagnose gdb issues

A few days ago, I installed the newest 64-bit gdb program (version 7.7.1) on Solaris 10 (X86_64 platform) to debug programs. After playing with the gdb a day, I found 2 issues about gdb:(1) The "set follow-fork-mode child" command doesn't take effect. By default, after the parent process forks the child process, the gdb will track the parent process, so this command can make gdb begin to follow the child process. But this command works OK on Linux.(2) The gdb can't parse the 32-bit application c...

   DTrace, debug, gdb, UNIX     2014-06-28 05:11:20

  How Can Your Data Be Stolen Online?

In 2019, according to Statista, nearly 165 million sensitive records were exposed in the US due to data breaches. Unfortunately, data theft is not going anywhere. Hackers are using increasingly sophisticated methods to steal information, but thankfully there are measures you can take to ensure your data stays safe. Here are some of the most common ways people get their data stolen online and how you can take precautions against the methods cybercriminals use. Human Error Hacking is one of the m...

   DATA SECURITY,PROTECTION KID     2021-01-27 19:46:05

  When will resizing be triggered in Java HashMap?

HashMap is one of the most frequently used collection types in Java, it stores key-value pairs. Ideally it expects to use hash table which expects the data access time complexity to be O(1), however, due to hash conflicts, in reality, it uses linked list or red-black tree to store data which makes the worst case time complexity to be O(logn).  Although collections are using data structures like arrays and linked lists, unlike arrays, they will dynamically resize when there is not enough spa...

   JAVA,RESIZE,HASHMAP,THRESHOLD     2020-05-02 20:41:19

  Exit main thread and keep other threads running in C

In C programming, if using return in main function, the whole process will terminate. To only let main thread gone, and keep other threads live, you can use thrd_exit in main function. Check following code: #include #include #include int print_thread(void *s) { thrd_detach(thrd_current()); for (size_t i = 0; i < 5; i++) { sleep(1); printf("i=%zu\n", i); } thrd_exit(0); } int main(void) { ...

   C LANGUAGE,MULITHREAD,MAIN THREAD     2020-08-14 21:20:04

  Add ContextMenu to a customized View in Android

In Android, we may sometimes need to add ContextMenu to a View, it's not so easy to add ContextMenu to a customized View. Here we explain how to add ContextMenu to a customized View. First, we may need to create View.OnCreateContextMenuListener so that the customized view can register for it. Here is the class definition: public class GraphView extends View {     private View.OnCreateContextMenuListener vC = new View.OnCreateContextMenuListener() {       &...

   Android, ContextMenu,Customized view     2012-11-04 07:10:40

  An experience of fixing a memory-corruption bug

During the last 4 months, I was disturbed by a memory-corruption bug, and this bug will cause program crash. Until last Monday, I found the root cause and fixed it. This debug process is a difficult but memorable experience, so I will share it in this article.   My program works as a SMS Hub. When it receives a SMS, it will allocate a structure in heap memory like this: typedef struct { ...... int *a[8]; ...... } info; After processing the SMS, the program will free the m...

   c, debug, unix, solaris, multi-thread     2014-05-04 03:52:43

  Go vs C benchmark. Could Go be faster than C?

During last semester I was attending Multiprocessor Architectures course, given at Facultad de Informática where I study my Computer Science degree. As part of the assignments due to pass the course, we had to do several programs written in C to benchmark matrix multiplication by testing different techniques and technologies. First of all we had to do a secuential program in three different versions: A normal one where the result matrix is ordered by rows and the loops range the matrix by ...

   Gp,C,Benchmark,Faster,Speed,Comparison     2012-02-08 10:09:07

  Bash Shell Scripting - 10 Seconds Guide

This Bash shell scripting guide is not a detailed study but a quick reference to the BASH syntax. So lets begin... Common environment variables PATH - Sets the search path for any executable command. Similar to the PATH variable in MSDOS. HOME - Home directory of the user. MAIL - Contains the path to the location where mail addressed to the user is stored. IFS - Contains a string of characters which are used as word seperators in the command line. The string normally consists of the spac...

   Bash,Shell,Linux,Tutorial,10 seconds,Shortcut key     2012-02-28 08:05:41

  Creating a PHP 5 Extension with Visual C++ 2005

This article describes the steps to create a custom PHP extension DLL for the Windows platform. The Zend API documentation that comes with PHP 5 on Windows (see php_manual_en.chm) does a good job explaining how to write extension methods, parse method parameters, and return values. But there is not currently a good step-by-step tutorial on how to get your first extension project up and running on Windows. The aim of this article is to fill that gap. Prerequisites Visual Studio 2005 You can...

   PHP,Extension,Writing,Windows,Step by st     2011-07-23 01:56:53

RECENT