Segmentation fault

[chc0613042124]

#include <stdio.h>
#include <unistd.h>
#include <stdlib.h>
#include <string.h>
#include <pthread.h>
#include <semaphore.h>

#define WORK_SIZE 256

void* thread_func(void *arg);

sem_t bin_sem;
char work_area[WORK_SIZE];

int main()
{
int ret = -1;
pthread_t thread_id;
void* thread_ret = NULL;

ret = sem_init(&bin_sem, 0, 0);
if (ret != 0)
{
perror("semaphore failed \n");
exit(EXIT_FAILURE);
}

ret = pthread_create(&thread_id, NULL, thread_func, NULL);
if (ret != 0)
{
perror("create thread failed\n");
exit(EXIT_FAILURE);
}

printf("input some text:");
while (strncpy("end", work_area, 3) != 0)
{
fgets(work_area, WORK_SIZE, stdin);
sem_post(&bin_sem);
}

printf("\nwaiting for thread to finish...");

ret = pthread_join(thread_id, &thread_ret);
if (ret != 0)
{
perror("thread join failed\n");
exit(EXIT_FAILURE);
}
printf("thread joined\n");

sem_destroy(&bin_sem);

return 0;
}


void* thread_func(void *arg)
{
sem_wait(&bin_sem);
while (strncpy("end", work_area, 3) != 0)
{
printf("you input %d characters\n", strlen(work_area)-1);
sem_wait(&bin_sem);
}
pthread_exit(NULL);
}

这段程序在LINUX下出现Segmentation fault，我想了半天也没想出来，请教各位

[zhonghaoqing]

段错误常见的错误有两种：

1 指针
2 访问了系统区

[dongjiawei316]

Segmentation fault表示你引用了无效指针，在出错前，还有别的打印信息吗？

[wuyu637]

gdb一步一步看是什么地方segment fault了，

[谭海燕]

while (strncpy("end", work_area, 3) != 0)

strncpy用错了你。

换成 strncpy(work_area, "end", 3)就好了


你的代码我改了strncpy（）之后，跑起来，已经正常了。

[love_rong]

你往一个只读内存区域("end")写东西。

[leaves2211]

"Segmentation fault"是段错误，内存访问错误，比如没有访问该内存地址的权限，往只读内存写数据，系统内存区地址等，或者访问malloc申请但是已经释放了的内存。