因为是串口输入，这个想法还是可以用的。

尽管最终再用性，可以屏蔽无用指令，虽然最后还是发了ascll码形式。

#include <sys/types.h> #include <sys/socket.h> #include <stdio.h> #include <stdlib.h> #include <arpa/inet.h> #include <netinet/in.h> #include <string.h> #include <unistd.h> #include <sys/stat.h> #include <fcntl.h>  int decoding(char *code) { 
          return -1; }  int main(int argc,char **argv) { 
           char code[4] = { 
        0};   int cmd = 0x01;    int s_fd;  struct sockaddr_in s_addr;    memset(&s_addr,0,sizeof(struct sockaddr_in));   s_fd = socket(AF_INET,SOCK_STREAM,0);  if(s_fd == -1){ 
           perror("socket");
		exit(-1);
	}

	s_addr.sin_family = AF_INET;
	s_addr.sin_port = htons(atoi(argv[2]));
	inet_aton(argv[1],&s_addr.sin_addr);	

	socklen_t len = sizeof(struct sockaddr_in);
	
	if(connect(s_fd,(struct sockaddr *)&s_addr,len) == -1){ 
        
		perror("connect");
		exit(-1);
	}

	while(1)
	{ 
        
		printf(">");
		memset(code,'\0',4);
		gets(code);	
		cmd = decoding(code);
		
		if(cmd == -1){ 
        
			printf("cmd not exist\n");
			continue; 
		}
		
		write(s_fd,code,4);
		if(cmd == 0xff){ 
        			
			close(s_fd);
			printf("client exit\n");
			exit(1);
		}	

	}
		
	return 0;
}