C threading in linux?

Question

Does someone have a simple example of threading in c?

I want to build a small console app that will read a txt file file line by line and then use threads to process the entire txt. How should I do this? splitting the txt into X where X=N of threads, is the first thing that comes to my mind, is there a better way?

Answer 1

Search for pthreads. I'm also a thread newbie. Here is a code snippet to sum from 1 to 1000000000 (also my first working pthread program).

#include <stdio.h>
#include <pthread.h>

struct arg {
    int a, b;
    int *rst;
};
typedef struct arg arg;

void* sum(void *);

int main()
{
    pthread_t sum1, sum2;
    int s1, s2;
    pthread_create(&sum1, NULL, sum, &(arg){1, 500000000, &s1});
    pthread_create(&sum2, NULL, sum, &(arg){500000001, 1000000000, &s2});   
    pthread_join(sum1, NULL);
    pthread_join(sum2, NULL);
    printf("%d\n", s1 + s2);
}

void* sum(void *ptr)
{
    int i, temp = 0;
    arg *x = ptr;

    for(i = x->a; i <= x->b; ++i)
        temp += i;
    *(x->rst) = temp;   
}

Answer 2

The best option IMHO is to use POSIX threads. You can see more details HERE.

Also please check the link in James' answer.

Answer 3

Search for POSIX threads, also known as pthreads. Tutorial Here