#ifndef __COMM_HPP_
#define __COMM_HPP_
#include <iostream>
#include <sys/ipc.h>
#include <sys/shm.h>
#include <cstdio>
#include <cstring>
#include <cstdlib>
using namespace std;
#define PATHNAME "."
#define PROJ_JD 0x66
#define MAX_SIZE 4096
key_t getkey()
{
    key_t k = ftok(PATHNAME,PROJ_JD);
    if(k <0)
    {
        cerr<<errno<<":"<<strerror(errno)<<endl;
        exit(1);
    }
    return k;
}
int getShmHelper(key_t k,int flags)
{
    //k是要shmget,设置进入共享内存属性中的，用来标识
    //该共享难内存在内核中的唯一性
    //shmid与key：
    //fd     inode
    int shmid = shmget(k,MAX_SIZE,flags);
    if(shmid<0)
    {
        cerr<<errno<<":"<<strerror(errno)<<endl;
        exit(2);
    }
    return shmid;
} 
//获取
int getShm(key_t k)
{
    return getShmHelper(k,IPC_CREAT);
}
//创建
int createShm(key_t k)
{
    return getShmHelper(k,IPC_CREAT | IPC_EXCL|0600);
}
void delShm(int shmid)
{
    if(shmctl(shmid,IPC_RMID,nullptr)==-1)
    {
        cerr<<errno<<":"<<strerror(errno)<<endl;
    }
}
void * attachShm(int shmid)
{
    void*mem = shmat(shmid,nullptr,0);
    if((long long)mem==-1L)//64位系统，8个字节，L表示数字类型
    {
        cerr<<errno<<"shmat:"<<strerror(errno)<<endl;
        exit(3);
    }
    return mem;
}
void detachShm(void * start)
{
    if(shmdt(start)==-1)
    {
        cerr<<"shmdt:"<<errno<<":"<<strerror(errno)<<endl;
    }
}
#endif

#include "comm.hpp"
#include <unistd.h>
using namespace std;
int main()
{
    key_t k = getkey();
    printf("key:%0x%x\n",k);
    int shmid = createShm(k);
    printf("shmid:%d\n",shmid);
    //sleep(5);
    char*start = (char*)attachShm(shmid);
    printf("attach success,address start:%p\n",start);
    //使用
    while(true)
    {
        printf("client say:%s\n",start);
        struct shmid_ds ds;
        shmctl(shmid,IPC_STAT,&ds);
        printf("获取属性：size:%d,pid:%d,myself:%d",ds.shm_segsz,ds.shm_cpid);
        sleep(1);
    }
    //去关联
    detachShm(start);
    sleep(10);
    //删除共享内存
    delShm(shmid);
    return 0;
}

#include "comm.hpp"
#include <unistd.h>
using namespace std;
int main()
{
    key_t k = getkey();
    printf("key:%0x%x\n",k);
    int shmid = getShm(k);
    printf("shmid:%d\n",shmid);
    char*start = (char*)attachShm(shmid);
    printf("attach success,address start:%p\n",start);
    const char*message = "hello server,我是另一个进程，正在和你通信";
    pid_t id = getpid();
    int count = 1;
    //char buffer[1024];
    while(true)
    {
       sleep(5);
       snprintf(start,MAX_SIZE,"%s[pid:%d][消息编号:%d]",message,id,count++);
       // snprintf(buffer,sizeof(buffer),"%s[pid:%d][消息编号:%d]",message,id,count++);
      //  memcpy(start,buffer,strlen(buffer)+1);
    }
    detachShm(start);
    return 0;
}

struct msqid_ds{
  struct ipc_perm msg_perm;
  time_t msg_stime;
  time_t msg_rtime;
  time_t msg_ctime;
  unsigned long __msg_cbytes;
  msgqnum_t msg_qnum;
  msglen_t msg_qbytes;
  pid_t msg_lspid;
  pid_t msg_lrpid;