Wrong thread IDs in a multithreaded C program?

Question

I am new to multithreading in C and I had this question. I wrote the following code:

#include 
#include 
#include 

        

Answer 1

You're passing the address of a variable the for is changing (i) so you're at the mercy of the scheduler. You should just pass a copy. As a cheap, not completely-kosher way:

pthread_create(&thread[i],&attr,test, (void*)i);

/* ... */

int i = (int)a;