linux C学习笔记02--共享内存

#include <signal.h>        //head file of define signal
#include <pthread.h>
#include <static_lib.h>
#include <errno.h>
#include <fcntl.h>
#include <unistd.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/types.h>
#include <sys/mman.h>

extern int create_shm(char **shmptr);
int main(int argc,char* argv[])
{
   //IPC share memory
    char *shmptr;
    if(create_shm(&shmptr) == -1)
    {
        printf("create_shm error \n");
        return -1;        
    }
    if(argc > 1)
    {
    //do the second thing for share memory
        while(1)
        {
            printf("input str to share memory:");
            gets(shmptr);
        }
    }
    else
    {
        memcpy(shmptr,"hello",5);
        while(1)
        {
            sleep(2);
            printf("share memory is %s \n",shmptr);
　　     }
    }   
    return 0;
}