a.c

Linux网络编程。通过建立共享内存

#include <unistd.h>
#include <stdlib.h>
#include <stdio.h>

#include <sys/types.h>
#include <sys/ipc.h>
#include <sys/shm.h>

#include "shm_com.h"

int main()
{
	int running=1;
	shm_data* shm_buff;
	int shmid;
	
	srand((unsigned int)getpid());
	
	shmid = shmget((key_t)1234, sizeof(shm_data), 0666|IPC_CREAT);//0666:user/group/other quan xian is r&w
	
	shm_buff = (shm_data *)shmat(shmid, (void*)0, 0);//hzg: '(void*)0' is auto alloc yingshe address.
	
	shm_buff->is_written=0;
	
	while (running){
		if (shm_buff->is_written)
		{
			printf ("You wrote : %s", shm_buff->data);
			//sleep(rand()%4);
			shm_buff->is_written=0;
			if (strncmp(shm_buff->data, "end", 3)==0)
				running=0;
		}
	}
	
	shmdt(shm_buff);
	
	shmctl(shmid, IPC_RMID, 0);
	
	exit(EXIT_SUCCESS);
	
}