#include <stdio.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <errno.h> 
#include <unistd.h> 

#define SERVER_PORT 7111
#define LEN_RECVBUFFER 1000
#define SERVER_IP_ADDRESS "127.0.0.1"

int main() {

    int sfd;
    struct  sockaddr_in saddr;
    pid_t childpid;
    size_t lenrecv, lensent, len, wlen;
    char recvbuffer[LEN_RECVBUFFER+1];
    char sendbuffer[LEN_RECVBUFFER];


    if ( 0 > ( sfd = socket(PF_INET,SOCK_STREAM,0) ) ) {
        perror("socket()-call");
        exit(1);
    }

    bzero((char *)&saddr,sizeof(saddr));
    saddr.sin_family = AF_INET;
    saddr.sin_addr.s_addr = inet_addr(SERVER_IP_ADDRESS);
    saddr.sin_port = htons(SERVER_PORT);

    if ( -1 == (connect(sfd,(struct sockaddr *)&saddr,sizeof(saddr) )) ) {
        perror("connect()-call");
        exit(1);
    }

    if ( 0 > (childpid = fork()) ) {
        perror("fork()-call");
        exit(1);
    }

    if ( !childpid ) {

        while ( 1 ) {

            if ( 0 > (lenrecv = read(sfd,recvbuffer,LEN_RECVBUFFER)) ) {
                perror("read()-call");
                exit(0);
            }

            if ( lenrecv > 0 ) {
                recvbuffer[lenrecv] = 0;
                printf("%s",recvbuffer);
                fflush(NULL);
            }

        }
              
    }

    while ( 1 ) {

        scanf("%s",sendbuffer);
        len = strlen(sendbuffer);
        sendbuffer[len] = '\n';
        sendbuffer[len+1] = 0;
        len = len + 1;
        lensent = 0;

        while ( lensent < len ) {

            if ( 0 > (wlen = write(sfd,
                                   &(sendbuffer[lensent]),
                                   len - lensent)) ) {
                perror("write()-call");
                exit(1);
            }

            lensent = lensent + wlen;

        }

        if ( !strncmp(sendbuffer,"STOP",sizeof("STOP")) ) {
            close(sfd);
            exit(0);
        }

    }

}