以下程序，两个程序通过共享内存通信，set.c是通过终端输入一个数字，然后通知get.c，get.c在终端显示出来，现在的问
题是，set后get.c无法显示数字，如果换成字符串则可以，不知道什么问题，高手帮忙看看！


/* set.c*/
#include 
#include 
#include 
#include 

#include 
#include 
#include 

#include "shm_com.h"

int main()
{
    int running = 1;
    void *shared_memory = (void *)0;
    struct shared_use_at *shared_stuff;
    char buffer[BUFSIZ];
    int shmid;
int command;

    shmid = shmget((key_t)1234, sizeof(struct shared_use_at), 0666 | IPC_CREAT);

    if(shmid == -1)
    {
        fprintf(stderr, "shmget failedn");
        exit(EXIT_FAILURE);
    }

    shared_memory = shmat(shmid, (void *)0, 0);
    if(shared_memory == (void *)-1)
    {
        fprintf(stderr, "shmat failedn");
        exit(EXIT_FAILURE);
    }

    printf("Memory attached at %Xn", (int)shared_memory);

    shared_stuff = (struct shared_use_at *)shared_memory;

    while(running)
    {
        while(shared_stuff->written_by_you == 1)
        {
            sleep(1);
            printf("waiting for client...n");
        }

        printf("Enter a number: ");
scanf("%dn", &command);
shared_stuff->power = command;
  /*      fgets(buffer, BUFSIZ, stdin);

        strncpy(shared_stuff->some_text, buffer, TEXT_SZ);*/
        
        shared_stuff->written_by_you = 1;

        if(command == 10)
        {
            running = 0;
        }
    }

    if(shmdt(shared_memory) == -1)
    {
        fprintf(stderr, "shmdt failedn");
        exit(EXIT_FAILURE);
    }

    exit(EXIT_SUCCESS);
}


/***************** get.c **************************/
#include 
#include 
#include 
#include 

#include 
#include 
#include 
#include "shm_com.h"

int main()
{
    int running = 1;
    void *shared_memory = (void *)0;
    struct shared_use_at *shared_stuff;
    int shmid;

    srand((unsigned int) getpid());

    shmid = shmget((key_t)1234, sizeof(struct shared_use_at), 0666|IPC_CREAT);

    if(shmid == -1)
    {
        fprintf(stderr, "shmget failedn");
        exit(EXIT_FAILURE);
    }


    shared_memory = shmat(shmid, (void *)0, 0);
    if(shared_memory == (void *)-1)
    {
        fprintf(stderr, "shmat failedn");
        exit(EXIT_FAILURE);
    }

    printf("Memory attached at %Xn", (int)shared_memory);


    shared_stuff = (struct shared_use_at *)shared_memory;
    shared_stuff->written_by_you = 0;
    while(running)
    {
        if(shared_stuff->written_by_you)
        {
            printf("You wrote: %s", shared_stuff->power);
            sleep(rand() % 4);
            shared_stuff->written_by_you = 0;
            if(shared_stuff->power==0)
            {
                running = 0;
            }
        }
    }


    if(shmdt(shared_memory)==-1)
    {
        fprintf(stderr, "shmdt failedn");
        exit(EXIT_FAILURE);
    }

    if(shmctl(shmid, IPC_RMID, 0)==-1)
    {
        fprintf(stderr, "shmctl(IPC_RMID) failedn");
        exit(EXIT_FAILURE);
    }

    exit(EXIT_SUCCESS);
}

          printf("You wrote: %s", shared_stuff->power); 

power是整数，为什么用%s ？