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What is the use of extern in c/c++?

Thursday, January 27th, 2011  »  Posted By  »  Total 0 Comment

The extern keyword is used to tell the compiler that a data object is declared in a different *.cpp or *.c file. So there wont be any new memory is allocated for these variables. Check the below example and understand the working. //file1.cpp #include <iostream.h>   int x; extern void func2();   void func1(void) { [...]

When we should use virtual destructor?

Tuesday, January 25th, 2011  »  Posted By  »  Total 0 Comment

It is used whenever a base class pointer is pointing to its derived class. In such a case when a user tries to delete the base class pointer then it results in deallocating the memory occupied by the base class.Therefore instead the derived class getting destroyed the base class does. Now as the base class [...]

How to allocate two dimensional array?

Wednesday, January 19th, 2011  »  Posted By  »  Total 0 Comment

Consider if you want to allocate a two dimensional array: int a[10][3]; Then you have to allocate the rows first and then columns using for loops. Here is the C example code. int **a, x; //Allocate memory a = malloc(sizeof(int *) * 10); for(x = 0; x &lt; 10; x ++) { a[x] = malloc(sizeof(int) [...]

How to run PHP files on localhost?

Thursday, June 4th, 2009  »  Posted By  »  Total 0 Comment

To run any php file you need to install Apache web server on your localhost. Also you need to install MySQL server for any database programming. You can install these separately or there is easy way to achieve the same by installing XAMPP. XAMPP is an easy to install Apache distribution containing MySQL, PHP and [...]

What is PHP?

Thursday, June 4th, 2009  »  Posted By  »  Total 0 Comment

PHP stands for “Hypertext Preprocessor“,  is a server-side scripting language used to create dynamic Web pages. This can be embedded to HTML pages. This is very easy scripting language compare to other scripting languags. The goal of the language is to allow Web developers to write dynamically generated pages quickly. PHP supports many databases like [...]

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