echo_client.c

Socket programming server/client

#include<stdio.h>
#include<stdlib.h>
#include<sys/socket.h>
#include<sys/types.h>
#include<netinet/in.h>
#include<strings.h>
#include<unistd.h>
#include<arpa/inet.h>
#include<string.h>

#define ERROR	-1
#define MAX_DATA	1024
int main(int argc, char **argv)
{
	if(argc < 3) { printf("./client ip port"); exit(-1);}
	int ser;
	// create a socket	
	if((ser = socket(AF_INET, SOCK_STREAM, 0)) == ERROR)
	{
		perror("server socket: ");
		exit(-1);
	}
/*
	struct sockaddr_in client;
	bzero(&client, sizeof(client));
	client.sin_family = AF_INET;
	client.sin_port = htons(12345);
	client.sin_addr.s_addr = INADDR_ANY;
	// bind a socket
	 if((bind(ser, (struct sockaddr *)&client, sizeof(client))) == ERROR)
	 {
	 perror("bind : ");
	 exit(-1);
	}
*/
	struct sockaddr_in server;
	bzero(&server, sizeof(server));
	server.sin_family = AF_INET;
	server.sin_addr.s_addr = inet_addr(argv[1]);
	server.sin_port = htons(atoi(argv[2]));
	// connect 
	if(connect(ser, (struct sockaddr*) &server, sizeof(server)) < 0)
	{
		perror("connect");
		exit(-1);
	}
	int rbyte;
	char rbuf[MAX_DATA];
	int rrbyte;
	char rrbuf[MAX_DATA];
	do
	{
		// read stdin
		rbyte = read(0, rbuf, MAX_DATA);
		if(rbyte > 0)
		{
			// write socket
			write(ser, rbuf, rbyte);
			// read socket
			rrbyte = read(ser, rrbuf, MAX_DATA);
			// write stdout
			write(1, rrbuf, rrbyte);

		} else {
			perror("read");
		}
		 
	}while(rbyte > 0);
	close(ser);
	return 0;
}