#include "sched.h" #include "pthread.h" #include "stdio.h" #include "stdlib.h" #include "semaphore.h" int producer(void * args); int consumer(void *args); pthread_mutex_t mutex; sem_t product; sem_t warehouse; char buffer[8][4]; int bp=0; main(int argc,char** argv) { pthread_mutex_init(&mutex,NULL); sem_init(&product,0,0); sem_init(&warehouse,0,8); int clone_flag,arg,retval; char *stack; clone_flag=CLONE_VM|CLONE_SIGHAND|CLONE_FS| CLONE_FILES; int i; for(i=0;i<2;i++) { //创建四个线程 arg = i; stack =(char*)malloc(4096); retval=clone((void*)producer,&(stack[4095]),clone_flag, (void*)&arg); stack =(char*)malloc(4096); retval=clone((void*)consumer,&(stack[4095]),clone_flag, (void*)&arg); } exit(1); } int producer(void* args) { int id = *((int*)args); int i; for(i=0;i<10;i++) { sleep(i+1); //表现线程速度差别 sem_wait(&warehouse); pthread_mutex_lock(&mutex); if(id==0) strcpy(buffer[bp],"aaa\0"); else strcpy(buffer[bp],"bbb\0"); bp++; printf("producer%d produce %s in %d\n",id,buffer[bp],bp-1); pthread_mutex_unlock(&mutex); sem_post(&product); } printf("producer%d is over!\n",id); } int consumer(void *args) { int id = *((int*)args); int i; for(i=0;i<10;i++) { sleep(10-i); //表现线程速度差别 sem_wait(&product); pthread_mutex_lock(&mutex); bp--; printf("consumer%d get %s in%d\n",id,buffer[bp],bp+1); strcpy(buffer[bp],"zzz\0"); pthread_mutex_unlock(&mutex); sem_post(&warehouse); } printf("consumer%d is over!\n",id); }这个代码在linu系统下有错误，应该如何修改

这份代码需要进行一些修改，才能在 Linux 系统下正常运行。以下是需要修改的地方：

1. `main` 函数没有返回类型，需要加上 `int`。

2. `producer` 和 `consumer` 函数需要加上返回类型，例如 `void*`。

3. 在 `for` 循环中创建线程时，需要传递一个指向 `int` 类型的指针作为参数，但是这里传递的是 `&arg`，应该改为 `(void*)&arg`。

4. `printf` 语句中的 `%s` 参数后面应该跟一个字符串，例如 `buffer[bp]`，而不是 `bp-1` 或 `bp+1`。

5. `strcpy` 函数需要传递一个字符串作为第二个参数，例如 `"aaa\0"`，而不是 `"aaa"`。

6. 在 `for` 循环中，`producer` 和 `consumer` 函数的调用顺序应该是先调用 `producer`，再调用 `consumer`。

7. 在 `main` 函数的最后，应该调用 `pthread_exit(NULL)`，而不是 `exit(1)`。

修改后的代码如下：

#include <sched.h>
#include <pthread.h>
#include <stdio.h>
#include <stdlib.h>
#include <semaphore.h>

int producer(void *args);
int consumer(void *args);

pthread_mutex_t mutex;
sem_t product;
sem_t warehouse;
char buffer[8][4];
int bp = 0;

int main(int argc, char** argv) {
    pthread_mutex_init(&mutex, NULL);
    sem_init(&product, 0, 0);
    sem_init(&warehouse, 0, 8);

    int clone_flag, arg, retval;
    char *stack;
    int i;

    for (i = 0; i < 2; i++) {
        arg = i;
        stack = (char*)malloc(4096);

        retval = clone(producer, &(stack[4095]), CLONE_VM | CLONE_SIGHAND | CLONE_FS | CLONE_FILES, (void*)&arg);

        stack = (char*)malloc(4096);
        retval = clone(consumer, &(stack[4095]), CLONE_VM | CLONE_SIGHAND | CLONE_FS | CLONE_FILES, (void*)&arg);
    }

    pthread_exit(NULL);
}

void* producer(void* args) {
    int id = *((int*)args);
    int i;
    for (i = 0; i < 10; i++) {
        sleep(i + 1);
        sem_wait(&warehouse);
        pthread_mutex_lock(&mutex);
        if (id == 0)
            strcpy(buffer[bp], "aaa\0");
        else
            strcpy(buffer[bp], "bbb\0");
        bp++;
        printf("producer%d produce %s in %d\n", id, buffer[bp - 1], bp - 1);
        pthread_mutex_unlock(&mutex);
        sem_post(&product);
    }
    printf("producer%d is over!\n", id);
    return NULL;
}

void* consumer(void* args) {
    int id = *((int*)args);
    int i;
    for (i = 0; i < 10; i++) {
        sleep(10 - i);
        sem_wait(&product);
        pthread_mutex_lock(&mutex);
        bp--;
        printf("consumer%d get %s in %d\n", id, buffer[bp], bp);
        strcpy(buffer[bp], "zzz\0");
        pthread_mutex_unlock(&mutex);
        sem_post(&warehouse);
    }
    printf("consumer%d is over!\n", id);
    return NULL;
}