C Articles - Page 67 of 134

Implicit ThreadingOne way to address the difficulties and better support the design of multithreaded applications is to transfer the creation and management of threading from application developers to compilers and run-time libraries. This, termed implicit threading, is a popular trend today.Implicit threading is mainly the use of libraries or other language support to hide the management of threads. The most common implicit threading library is OpenMP, in context of C.OpenMP is a set of compiler directives as well as an API for programs written in C, C++, or FORTRAN that provides support for parallel programming in shared-memory environments. OpenMP identifies ... Read More

Threads are created in the Windows API using the CreateThread() function, and—just as in Pthreads—a set of attributes like security information, the size of the stack, and a flag for the thread is passed to this function. In the below program, we use the default values for these attributes. (The default values do not initially set the thread to a suspended state and instead make it eligible to be run by the CPU scheduler.) Once the summation thread is created, the parent must wait for it to complete before outputting the value of Sum, as the value is set by ... Read More

In the C programming language, there is an option to create an arc of a circle of a given radius with a given center coordinates and degree of the arc.The arc() function is used to create an arc. This arc function is included in graphics.h library in C which contains methods that can draw figures on the output screen.Syntaxvoid arc(int x, int y, int startangle, int endangle, int radius);Now, let's get deep into the function and understand each parameter passed and output returned by the function.Parametersx − type = int, function: defines the x coordinate of the center of the arc.y ... Read More

Divide and conquer is an algorithm that works on the paradigm based on recursively branching problem into multiple sub-problems of similar type that can be solved easily.ExampleLet’s take an example to learn more about the divide and conquer technique −function recursive(input x size n)    if(n < k)       Divide the input into m subproblems of size n/p.       and call f recursively of each sub problem    else       Solve x and returnCombine the results of all subproblems and return the solution to the original problem.Explanation − In the above problem, the problem ... Read More

Grand Central Dispatch (GCD) - a technology for Apple’s Mac OS X and iOS operating systems-is a combination of extensions to the C language, an API, and a run-time library that allows application developers to identify sections of code to run in parallel. Like OpenMP, GCD manages most of the details of threading. GCD identifies extensions to the C and C++ languages known as blocks. A block is simply a self-contained unit of work. It is specified by a caret ˆ inserted in front of a pair of braces { }. A simple example of a block is shown below ... Read More

OpenMP is a set of compiler directives as well as an API for programs written in C, C++, or FORTRAN that provides support for parallel programming in shared-memory environments. OpenMP identifies parallel regions as blocks of code that may run in parallel. Application developers insert compiler directives into their code at parallel regions, and these directives instruct the OpenMP run-time library to execute the region in parallel. The following C program illustrates a compiler directive above the parallel region containing the printf() statement −#include #include int main(int argc, char *argv[]){    /* sequential code */    #pragma omp ... Read More

Windows anonymous pipes are actually Ordinary pipes, and they behave similarly to their UNIX counterparts: they are unidirectional and employ parent-child relationships between the communicating processes. In addition, reading and writing to the pipe can be accomplished with the ordinary ReadFile() and WriteFile() functions. The Windows API use CreatePipe() function for creating pipes, which is passed four parameters. The parameters provide separate handles forreading andwriting to the pipeAn instance of the STARTUPINFO structure, used to specify that the child process is to inherit the handles of the pipe.the size (in Bytes) of the pipe may be specified.Windows requires the programmer ... Read More

A Pointer is a variable that stores the address of another variable. The data type of the pointer is the same as the data type as the variable.In this puzzle you need to know the size of the pointer that is being used. The puzzle checks our understanding of pointers by asking you the size of variable.The size of int is 4 bytes, whereas the size of int pointer is 8. Now, let’s test your skills with the following exercise in c++ programming language.Example Live Demo#include using namespace std; int main() {    int a = 6 ;    int ... Read More

This C/C++ function call puzzle is a puzzle that is intended to explore more about the behaviour of method calling in both the programming languages C and C++/.The output of a method in C and C++ is different. Lets see what is the difference in calling methods in C and C++.Let’s take an example and check the output of the below code in c and c++.Example Live Demovoid method() {    // Print statement } int main() {    method();    method(2); }OutputFor C++ −Error : too many arguments to function ‘void method()’For C −Program runs without any error.Logic behind the ... Read More

C Files I/O − Create, Open, Read, Write and Close a File C File management A File can be used to store a large volume of persistent data. Like many other languages 'C' provides the following file management functions, Creation of a file Opening a file Reading a file Writing to a file Closing a file Following are the most important file management functions available in 'C, ' function ... Read More