void mainloop() {
int sockfd, fd;
struct sockaddr_in sa;
socklen_t n;

sockfd = socket(AF_INET, SOCK_STREAM, IPPROTO_IP);
if(sockfd != - 1 ) {
memset(&sa,  0 , sizeof(sa));

sa.sin_family = AF_INET;
sa.sin_addr.s_addr = htonl(INADDR_ANY);
sa.sin_port = htons( 55555 );

if(bind(sockfd, (struct sockaddr *) &sa, sizeof(sa)) != - 1 ) {
while( 1 ) {
if(!listen(sockfd, SOMAXCONN)) {
n = sizeof(sa);
if((fd = accept(sockfd, (struct sockaddr *) &sa, &n)) != - 1 ) {
syslog(LOG_NOTICE, "connection from %s", inet_ntoa(sa.sin_addr));
{
pthread_t thread;
pthread_create(&thread, NULL, operate, (void*)fd);//тут и передает 
pthread_detach(thread);
}
}
}
}
}
}
}

 void *operate(void *_fd) {
int* fd2=(int*)_fd;
int fd=(int)fd2;
char c;
bool finished;
string cmd, answer, stmp="", Login, Passwd, answer2="";
char* tmp;
int IDtmp= 0 ,itmp= 0 ,UserNum= 0 ,i;
syslog(LOG_NOTICE,"SocketConnected=%d",fd);
finished = false;

answer = "the simple tcp daemon is ready";
write(fd, answer.c_str(), answer.size());//- это клиент получает

while(!finished) {
cmd = answer = "";

/* Read a line from the client side*/

while(!finished) {
finished = read(fd, &c,  1 ) !=  1 ;

if(c == '\n') break; else
if(c != '\r') cmd += c;
}

/* If there is a command and no socket error appeared in the previous cycle, try to perform some processing.*/

if(!finished && !cmd.empty()) {
syslog(LOG_NOTICE,"cmd=%s from Socket: %d",cmd.c_str(),fd);
if(cmd == "hello") {
answer = "my daemonic greatings";
} else if(cmd == "version") {
answer = "Verision 0.0001 = Alpha. Mega-Message-Server";
} else if(cmd == "quit") {
shutdown(fd,  2 );
close(fd);
finished = true;
}

if(!finished && !answer.empty()) {
	    //answer += "\n";
	    write(fd, answer.c_str(), answer.size());
	}