关于共享内存的的问题~

[bm1408]

最近在弄一个程序，要使用共享内存,要求很简单，就是父进程写进信息，子进程读出来
大家给一个例子吧
比如说：

struct student
{
int id;
char name[`11];
}STU[MAX]；

父进程把这个结构体信息放入共享内存中，然后子进程读出并修改，
大家给个例子~~~

[字与码]

#include <stdlib.h>
#include <sys/shm.h>

#define ARRAY_SIZE 40000
#define MALLOC_SIZE 100000
#define SHM_SIZE 100000
#define SHM_MODE 0600 /* user read/write */

char array[ARRAY_SIZE]; /* uninitialized data = bss */

int
main(void)
{
int shmid;
char *ptr, *shmptr;

printf("array[] from %lx to %lx\n", (unsigned long)&array[0],
(unsigned long)&array[ARRAY_SIZE]);
printf("stack around %lx\n", (unsigned long)&shmid);

if ((ptr = malloc(MALLOC_SIZE)) == NULL)
printf("malloc error\n");
printf("malloced from %lx to %lx\n", (unsigned long)ptr,
(unsigned long)ptr+MALLOC_SIZE);

if ((shmid = shmget(IPC_PRIVATE, SHM_SIZE, SHM_MODE)) < 0)
printf("shmget error\n");
if ((shmptr = shmat(shmid, 0, 0)) == (void *)-1)
printf("shmat error\n");
printf("shared memory attached from %lx to %lx\n",
(unsigned long)shmptr, (unsigned long)shmptr+SHM_SIZE);

if (shmctl(shmid, IPC_RMID, 0) < 0)
printf("shmctl error\n");

exit(0);
}