chap5 echo_client2.c

#include <stdio.h>

#include <stdlib.h>

#include <string.h>

#include <unistd.h>

#include <arpa/inet.h>

#include <sys/socket.h>

#define BUF_SIZE 1024

void error_handling(char *message);

int main(int argc, char *argv[])

{

int sock;

char message[BUF_SIZE];

int str_len, recv_len, recv_cnt;

struct sockaddr_in serv_adr;

if(argc!=3) {

printf("Usage : %s <IP> <port>\n", argv[0]);

exit(1);

}

sock=socket(PF_INET, SOCK_STREAM, 0);   

if(sock==-1)

error_handling("socket() error");

memset(&serv_adr, 0, sizeof(serv_adr));

serv_adr.sin_family=AF_INET;

serv_adr.sin_addr.s_addr=inet_addr(argv[1]);

serv_adr.sin_port=htons(atoi(argv[2]));

if(connect(sock, (struct sockaddr*)&serv_adr, sizeof(serv_adr))==-1)

error_handling("connect() error!");

else

puts("Connected...........");

while(1) 

{

fputs("Input message(Q to quit): ", stdout);

fgets(message, BUF_SIZE, stdin);

if(!strcmp(message,"q\n") || !strcmp(message,"Q\n"))

break;

str_len=write(sock, message, strlen(message));

recv_len=0;

while(recv_len<str_len)

{

recv_cnt=read(sock, &message[recv_len], BUF_SIZE-1);

if(recv_cnt==-1)

error_handling("read() error!");

recv_len+=recv_cnt;

}

message[recv_len]=0;

printf("Message from server: %s", message);

}

close(sock);

return 0;

}

void error_handling(char *message)

{

fputs(message, stderr);

fputc('\n', stderr);

exit(1);

}