c - 使用 C 中的线程写入全局文件

Question

我在写入全局创建的文件、在 main 中初始化(成功)以及写入多个线程使用的函数(在 Linux 上)时遇到问题。

#includes

FILE *f;
main(){
    // Create threads successfully
    f = fopen("fileName.txt", "w");
    // Make sure the file was able to be created
    if(f = NULL){
          printf("Unable to create file");
          exit(1);
     }
     // This much works, the check indicates the file was created 
     // successfully when I run it
     while(1){
         // loops for a while, getting input from user to direct threads
         // When end is determined, waits for all the threads to finish,
         // clears allocated memory, and closes file then returns
         fclose(f);
         return;
     }


}

void *threadProcess(){
    // Do stuff
    // This printf works fine using the values i give the function, as is here
    // The values are determined in 'Do stuff'
    printf("%d trying to write \"%d BAL %d TIME %d.%06d %d.%06d\" to the file\n", cid, tmp->reqNum, balance, tmp->seconds, tmp->useconds, endTime.tv_sec, endTime.tv_usec);
    fflush(stdout);

    // There appears to be a Segmentation fault here
    fprintf(f, "%d BAL %d TIME %d.%06d %d.%06d\n", tmp->reqNum, balance, tmp->seconds, tmp->useconds, endTime.tv_sec, endTime.tv_usec);
    // Never gets here
}

我在这里做错了什么？正如我所说，fprintf 语句之前的 printf 语句有效并输出正确的内容。

我是否错误地假设这将确保我不会遇到 fprintf 的指针问题？

谢谢

Answer 1

它在我的 if(reqLog = NULL) 检查中......我正在分配而不是比较。抱歉浪费了您的时间哈哈。 – 汤普森