Question

我目前正在尝试从其他线程创建线程。当我的线程试图加入时，我得到一个段错误

这是我的主要功能：

from itertools import groupby

data = (k.rstrip().split("=Cluster=") for k in open("f_input.txt", 'r'))
final = list(k for k,_ in groupby(list(data)))

with open("new_file.txt", 'a') as f:
    for k in final:
        if k == ['','']:
            f.write("=Cluster=\n")
        elif k == ['']:
            # write '\n\n' in Windows and '\n' in Linux (tested only in Windows!)
            f.write("\n\n")
        else:
            f.write("{}\n".join(k))

和我的帖子主要：

new_file.txt

运行valgrind会给我错误：

int main( int argc, char *argv[] ) {
    std::cout<< "start" << std::endl;
    init();
    std::cout<<"finished init" << std::endl;
    t1=clock();
    pthread_t threads[THREAD_COUNT];

    for (int i = 0; i < THREAD_COUNT; i++) {
        pthread_create(&threads[i], NULL, &threadMain, (void*)((long)i));
    }

    for (int i = 0; i < THREAD_COUNT; i++) {
        printf("joining %d \n" , i);
        pthread_join(threads[i], NULL);
    }
    timeEnd();


    return(0);
}

每当我在ubuntu机器上运行它时，我都会遇到分段错误。使用gdb，在pthread_join中放置一个断点并单步执行最终会给我一个段错误。

在Mac上运行它，我得到以下输出：

./ a.out

开始

完成初始化

加入0

a.out（3473,0x10c61e000）malloc： *对象0x7f97fa5016f0的错误：未释放指针被释放   * 在malloc_error_break中设置断点以进行调试

中止陷阱：6

修改

一些定义：

void *threadMain(void *arg) {
long thread = (long) arg;

volatile int *tix;
tix = (volatile int *)malloc(sizeof(volatile int) * INNER_THREADS);
volatile int *c;
c =  (volatile int *)malloc(sizeof(volatile int) * INNER_THREADS);
volatile int r;

memset((void*)tix, 0, sizeof(tix));
memset((void*)c, 0, sizeof(c));
r = 0;


pthread_t threads[INNER_THREADS];


for (int i = 0; i < INNER_THREADS; ++i) {
    vec[i+thread*2] = new desc();
    vec[i+thread*2]->outterThread = thread;
    vec[i+thread*2]->innerThread = i;
    vec[i+thread*2]->tix = tix;
    vec[i+thread*2]->c = c;
    vec[i+thread*2]->r = &r;
    pthread_create(&threads[i], NULL, &threadBody, (void*) vec[i+thread*2]);


}

for (int i = 0; i < INNER_THREADS; ++i) {
    pthread_join(threads[i], NULL);
}


return 0;
}

Answer 1

请添加缺少的详细信息来完成您的程序：threadBody（），init（），clock（）＆amp; timeEnd（）或删除它们，如果它们与面临的问题无关。

我可以通过删除/假设一些缺失的细节来准备代码： http://pastebin.com/j5a9whdR

工作正常。

$ ./a.out | sort
joining outer thread 0
joining outer thread 1
joining outer thread 2
joining outer thread 3
joining outer thread 4
joining outer thread 5
joining outer thread 6
joining outer thread 7
joining outer thread 8
joining outer thread 9
Outer thread 0 Inner thread 0
Outer thread 0 Inner thread 1
Outer thread 1 Inner thread 0
Outer thread 1 Inner thread 1
Outer thread 2 Inner thread 0
Outer thread 2 Inner thread 1
Outer thread 3 Inner thread 0
Outer thread 3 Inner thread 1
Outer thread 4 Inner thread 0
Outer thread 4 Inner thread 1
Outer thread 5 Inner thread 0
Outer thread 5 Inner thread 1
Outer thread 6 Inner thread 0
Outer thread 6 Inner thread 1
Outer thread 7 Inner thread 0
Outer thread 7 Inner thread 1
Outer thread 8 Inner thread 0
Outer thread 8 Inner thread 1
Outer thread 9 Inner thread 0
Outer thread 9 Inner thread 1
$

除了一些内存泄漏外，valgrind也很开心。

有一点需要提及：'2'（在vec [i + thread * 2]和vec [THREAD_COUNT * 2]）的使用应该用INNER_THREADS替换。

主要问题是threadBody（）函数是什么？

Answer 2

长线程=（长）*线程不应该只用“（长）线程。我指的是你的threadMain函数的第一行

pthread_join错误，从线程创建线程

2 个答案: