https://medjava.ro/ 2026-04-08T07:44:33+00:00 https://medjava.ro/ https://medjava.ro/lib/exe/fetch.php?media=wiki:dokuwiki.svg text/html 2025-01-02T18:22:18+00:00 Anonymous (anonymous@undisclosed.example.com) https://medjava.ro/doku.php?id=c:pthreads:barrier-odd-even-transposition-sort&rev=1735842138&do=diff Odd Even Transposition Sort (Parallel Bubble Sort) Using Pthreads and Barrier #include <stdio.h> #include <stdlib.h> #include <pthread.h> #define NUM_THREADS 4 // Number of threads (should be even) #define ARRAY_SIZE 8 // Size of the array int array[ARRAY_SIZE]; pthread_barrier_t barrier; // Function to swap two array elements void swap(int *a, int *b) { int temp = *a; *a = *b; *b = temp; } // Function executed by each thread void *sort(void *arg) { int thread_part = *(i… text/html 2025-01-02T18:22:18+00:00 Anonymous (anonymous@undisclosed.example.com) https://medjava.ro/doku.php?id=c:pthreads:barrier-shear-sort-parallel&rev=1735842138&do=diff Shear Sort Using Pthreads and Barrier #include <stdio.h> #include <stdlib.h> #include <unistd.h> #include <pthread.h> #define MATRIX_SIZE 4 // Size of the matrix (example 4x4) #define NUM_THREADS (MATRIX_SIZE * 2) // Number of threads for matrix's rows and columns int matrix[MATRIX_SIZE][MATRIX_SIZE]; pthread_barrier_t barrier; // Function to swap two elements void swap(int *a, int *b) { int temp = *a; *a = *b; *b = temp; } // Function executed by each thread to sort a row or… text/html 2025-01-02T18:22:18+00:00 Anonymous (anonymous@undisclosed.example.com) https://medjava.ro/doku.php?id=c:pthreads:barrier-simulate-work&rev=1735842138&do=diff Pthread barrier example - simulate work then wait at barrier #include <stdio.h> #include <stdlib.h> #include <unistd.h> #include <pthread.h> #define NUM_THREADS 5 // Number of threads // Barrier variable pthread_barrier_t barrier; // Function executed by each thread void *thread_work(void *tid) { long my_tid = (long)tid; printf("Thread %ld is doing some work before the barrier\n", my_tid); // Simulate some work sleep(1); // Sleep for a second to simulate work // Wait … text/html 2025-01-02T18:22:18+00:00 Anonymous (anonymous@undisclosed.example.com) https://medjava.ro/doku.php?id=c:pthreads:binary-search-parallel&rev=1735842138&do=diff Parallel Binary Search Using Pthreads #include <stdio.h> #include <stdlib.h> #include <pthread.h> #define ARRAY_SIZE 16 // Size of the array #define NUM_THREADS 4 // Number of threads #define TARGET 7 // Number to search for int array[ARRAY_SIZE]; int found = -1; // Index of the found element (-1 if not found) // Struct for passing data to threads typedef struct { int low; int high; } SearchRange; // Function executed by the thread void *binary_search_thread(void *arg) { … text/html 2025-01-02T18:22:18+00:00 Anonymous (anonymous@undisclosed.example.com) https://medjava.ro/doku.php?id=c:pthreads:hello-world&rev=1735842138&do=diff Pthreads Hello World #include <stdio.h> #include <stdlib.h> #include <pthread.h> // This function will be executed by each thread void *print_hello_world(void *tid) { // Print the thread's ID and a message printf("Hello World! Thread ID: %ld\n", (long)tid); pthread_exit(NULL); // Exit the thread } int main(int argc, char *argv[]) { pthread_t threads[5]; // Array to store thread IDs int status; // For storing return value of pthread_create long i; … text/html 2025-01-02T18:22:18+00:00 Anonymous (anonymous@undisclosed.example.com) https://medjava.ro/doku.php?id=c:pthreads:makefile&rev=1735842138&do=diff Makefile to compile a pthread app in C # Target for building the program build: hello # Rule for building the 'hello' executable from 'hello.c' hello: hello.c gcc hello.c -o hello -lpthread # Phony target for cleaning up .PHONY: clean clean: rm -f hello text/html 2025-01-02T18:22:18+00:00 Anonymous (anonymous@undisclosed.example.com) https://medjava.ro/doku.php?id=c:pthreads:merge-sort-parallel&rev=1735842138&do=diff Merge Sort Using Pthreads #include <stdio.h> #include <stdlib.h> #include <pthread.h> #define ARRAY_SIZE 8 // Size of the array #define NUM_THREADS 2 // Number of threads int array[ARRAY_SIZE]; // Struct for passing data to threads typedef struct { int low; int high; } SortRange; // Function to merge two halves of an array void merge(int low, int mid, int high) { int n1 = mid - low + 1; int n2 = high - mid; int left[n1], right[n2]; // Copy data to temp arrays lef… text/html 2025-01-02T18:22:18+00:00 Anonymous (anonymous@undisclosed.example.com) https://medjava.ro/doku.php?id=c:pthreads:mutex-barrier-array-sum&rev=1735842138&do=diff Compute the sum of an array elements in parallel using pthread with mutex and barrier #include <stdio.h> #include <stdlib.h> #include <pthread.h> #define NUM_THREADS 4 // Number of threads #define ARRAY_SIZE 100 // Size of the array int array[ARRAY_SIZE]; int total_sum = 0; pthread_mutex_t sum_mutex; pthread_barrier_t sum_barrier; // Function for each thread to compute part of the sum void *partial_sum(void *arg) { int thread_part = *(int*)arg; int local_sum = 0; // Calculate… text/html 2025-01-02T18:22:18+00:00 Anonymous (anonymous@undisclosed.example.com) https://medjava.ro/doku.php?id=c:pthreads:mutex-shared-variable&rev=1735842138&do=diff Using mutex in pthread to access a shared variable #include <stdio.h> #include <stdlib.h> #include <pthread.h> // Global variable and mutex int shared_variable = 0; pthread_mutex_t mutex; // Function to be executed by threads void *update_shared_variable(void *arg) { pthread_mutex_lock(&mutex); // Lock the access to the variable shared_variable++; // Update the shared variable printf("Updated value: %d\n", shared_variable); pthread_mutex_unlock(&mutex); // Unlock … text/html 2025-01-02T18:22:18+00:00 Anonymous (anonymous@undisclosed.example.com) https://medjava.ro/doku.php?id=c:pthreads:parallel-increment-vector&rev=1735842138&do=diff Increment elements of a vector in parallel using pthreads Parallelize the incrementing of elements in a 100-element array. This will involve dividing the addition iteration among all threads in the most equitable way possible. #include <stdio.h> #include <stdlib.h> #include <pthread.h> #define NUM_THREADS 4 // Number of threads to use #define VECTOR_SIZE 100 // Size of the array // Structure to pass information to threads typedef struct { int start; // Starting index for this thread …