Book Image

Extreme C

By : Kamran Amini
5 (2)
Book Image

Extreme C

5 (2)
By: Kamran Amini

Overview of this book

There’s a lot more to C than knowing the language syntax. The industry looks for developers with a rigorous, scientific understanding of the principles and practices. Extreme C will teach you to use C’s advanced low-level power to write effective, efficient systems. This intensive, practical guide will help you become an expert C programmer. Building on your existing C knowledge, you will master preprocessor directives, macros, conditional compilation, pointers, and much more. You will gain new insight into algorithm design, functions, and structures. You will discover how C helps you squeeze maximum performance out of critical, resource-constrained applications. C still plays a critical role in 21st-century programming, remaining the core language for precision engineering, aviations, space research, and more. This book shows how C works with Unix, how to implement OO principles in C, and fully covers multi-processing. In Extreme C, Amini encourages you to think, question, apply, and experiment for yourself. The book is essential for anybody who wants to take their C to the next level.
Table of Contents (23 chapters)

Example of data race

Example 15.3 demonstrates a data race. In previous examples, we didn't have a shared state, but in this example, we are going to have a variable shared between two threads.

The invariant constraint of this example is to protect the data integrity of the shared state, plus all other obvious constraints, like having no crashes, having no bad memory accesses, and so on. In other words, it doesn't matter how the output appears, but a thread must not write new values while the value of the shared variable has been changed by the other thread and the writer thread doesn't know the latest value. This is what we mean by "data integrity":

#include <stdio.h>
#include <stdlib.h>
// The POSIX standard header for using pthread library
#include <pthread.h>
void* thread_body_1(void* arg) {
  // Obtain a pointer to the shared variable
  int* shared_var_ptr = (int*)arg;
  // Increment the shared variable by 1 by writing
  // directly...