[問題] pthread 的 race condition
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遇到的問題： (題意請描述清楚)
在Linux底下希望能寫個有 race condition 的範例程式
但是程式怎麼跑都是正確的結果
想請問為什麼跑不出 race condition 的情形
開發平台： Ubuntu 9.04 desktop
有問題的code：
#include <stdio.h>
#include <pthread.h>
#define NTHREADS 100
void *thread_function(void *);
int counter = 0;
int main()
{
pthread_t thread_id[NTHREADS];
int i, j;
for (i = 0; i < NTHREADS; i++) {
pthread_create(&thread_id[i], NULL, thread_function, NULL);
}
for (j = 0; j < NTHREADS; j++) {
pthread_join(thread_id[j], NULL);
}
/* Now that all threads are complete I can print the final result. */
/* Without the join I could be printing a value before all the threads */
/* have been completed. */
printf("Final counter value: %d\n", counter);
}
void *thread_function(void *dummyPtr)
{
printf("Thread number %ld\n", pthread_self());
counter++;
}
補充說明：
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