/******write.c******/
# include <sys/ipc.h>
# include <sys/shm.h>
# include <sys/types.h>
# include <unistd.h>
typedef struct{
char name[4];
int age;
} people;
main(int argc,char** argv)
{
int shm_id,i;
int shmdt_id;
key_t key;
char temp;
people *p_map;
char* name = ".";
key = ftok(name,0);
if (key == -1)
{
perror("ftok error");
return;
}
shm_id = shmget(key,4096,IPC_CREAT); //调用shmget创建一块共享主存区
if (shm_id == -1)
{
perror("shmget error");
return;
}
p_map = (people*)shmat(shm_id,NULL,0);//将共享主存区附加到自己的主存段
temp = 'a';
for (i = 0 ;i < 10 ; i++ ) //向共享主存中写入数据
{
temp = temp + 1;
memcpy((*(p_map + 1)).name,&temp,1);
(*(p_map+i)).age = 20 + i;
}
shmdtid = shmdt(p_map); //将其从自己的主存段中“删除”出去
if(shmdtid == -1) //删除失败
{
perror("detach error");
return;
}
}
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