修改后的dg_cli

void dg_cli(FILE *fp, int sockfd, const struct sockaddr * pservaddr, socklen_t servlen) {
    int n;
    char sendline[maxline], recvline[maxline+1];
    char errbuff[maxline];
    struct sockaddr_in localaddr;
    socklen_t len=sizeof(localaddr);
 
    if(connect(sockfd, (struct sockaddr *)pservaddr, servlen)<0) {
        strerror_r(errno, errbuff, maxline);
        fprintf(stderr, "connect error: %s\n", errbuff);
        exit(-1);
    }
 
    while(fgets(sendline, maxline, fp) != NULL) {
        if((n=write(sockfd, sendline, strlen(sendline)))<0) {
            strerror_r(errno, errbuff, maxline);
            fprintf(stderr, "write error: %s\n", errbuff);
            exit(-1);
        }
 
        if(read(sockfd, recvline, maxline) != n) {
            strerror_r(errno, errbuff, maxline);
            fprintf(stderr, "read error: %s\n", errbuff);
            exit(-1);
        }
        if(getsockname(sockfd, (struct sockaddr *)&localaddr, &len)<0) {
            strerror_r(errno, errbuff, maxline);
            fprintf(stderr, "getsockname error: %s\n", errbuff);
            exit(-1);
        }
        recvline[n]=0;
        fputs(recvline, stdout);
        printf("local ip: %s, local port: %d\n", inet_ntop(AF_INET, &localaddr.sin_addr, errbuff, sizeof(errbuff)), ntohs(localaddr.sin_port));     
    }
}