void Start_Server()
        {
                struct sockaddr_in serv;
                struct sockaddr_in cli;
                socklen_t client_len;
                //char username[10];
                char bufer[30]={0};
                char *buf="Connection Successful";
                char cPassword[20];

                pthread_t threadID;
                int nListenDesc;                                        // server socket descriptor
                int nConnectionDesc=-1;                                 // client socket descriptor
                int nRetvalue;                                          //storing return value of authentication

                nListenDesc=socket(AF_INET,SOCK_STREAM,0);
                serv.sin_family=AF_INET;
                serv.sin_addr.s_addr=inet_addr(IP);                     // assigning ip address
                serv.sin_port=htons(PORT);                              //assigning port address
                if(nListenDesc==-1)
                        perror("socket descriptor not created");
                bind(nListenDesc,(struct sockaddr*)&serv,sizeof(serv)); //assigning address to socket
                if((system("mkdir /tmp/monitor/"))==-1)                 // creating directory
                        puts("directory not created");
                listen(nListenDesc,5);
                while(1)
                {   if((nConnectionDesc = accept(nListenDesc,(struct sockaddr*)&cli,&client_len))==-1)
                                perror("error in nConnectionDesc");
                        recv(nConnectionDesc,bufer,strlen(bufer),0);
                        puts(bufer);
                        sscanf(bufer,"%s %s",cUsername,cPassword);
                        printf("%s %s",cUsername,cPassword);
                        if((nRetvalue=authenticate(cUsername,cPassword,nConnectionDesc))==1)    // passing username and password for
                        {                                                       // authentication
                                puts("user not authenticated ");
                                exit(0);
                        }

                        send(nConnectionDesc,buf,strlen(buf),0);
                        if (pthread_create(&threadID, NULL, &serverThread,(void *) nConnectionDesc) != 0) //creating thread
                        {
                                perror("Thread create error");
                                close(nConnectionDesc);
                                close(nListenDesc);
                                exit(1);
                        }
                        //pthread_detach(pthread_self());
                        printf("Parent ready for another connectionn");


                }



int authenticate(char cUser[20],char cPass[20],int nAsock)
{
        struct loginStruct sAuthent[10];        //creating object of loginStruct
        int nIndex=0;
        int nFiledesc;                          //file descriptor

        strcpy(sAuthent[0].cUname,"aviral");    // passing value to
        strcpy(sAuthent[0].cPaswd,"aviral");    // structure variables
        strcpy(sAuthent[1].cUname,"avinash");
        strcpy(sAuthent[1].cPaswd,"avinash");
        for(; nIndex<3;nIndex++)
        {
                if(strcmp(cUser,sAuthent[nIndex].cUname) ==0)   // authenticate username
                {
                        if(strcmp(cPass,sAuthent[nIndex].cPaswd)==0) //authenticate password
                        {
                                puts("cUser good");
                                char cPath[20]="/tmp/monitor/";
                                strcat(cPath,cUser);
                                puts(cPath);
                                nFiledesc=creat(cPath,S_IRWXU);         //creating user file
                                close(nFiledesc);
                                return 0;
                        }

                }
                else
         {
                //      puts("User not Authenticates");

                }


        }       return 1;

}

void Start_Client()
    {
            struct sockaddr_in serv;
            int sock=-1;
            sock=socket(AF_INET,SOCK_STREAM,0);
            memset(&serv,0,sizeof(struct sockaddr_in));
            serv.sin_family=AF_INET;
            serv.sin_addr.s_addr=inet_addr(IP);
            serv.sin_port=htons(PORT);
            if(sock==-1)
                    perror("Socket not created");
            if((connect(sock, (struct sockaddr*)&serv,sizeof(serv)))!=0)

                    perror("connection not established");
            login(sock);
            transact_with_serv(sock);
    }
    int login()
    {
                    char carUser[20];
                    char carPass[20];
                    int sockfd,n;
                    char buff[20];
                    printf("Enter username:");
                    scanf("%s",carUser);
                    printf("Enter Password:");
                    scanf("%s",carPass);
                    sprintf(buff,"%s %s",carUser,carPass);
                    send(sockfd,buff,strlen(buff),0);
                    n=recv(sockfd,buff,sizeof(buff),0);
                    puts(buff);
                    return sockfd;
    }

nConnectionDesc = accept(nListenDesc,(struct sockaddr*)&cli,&client_len)

client_len = sizeof(cli);

char bufer[30]={0};
....
recv(nConnectionDesc,bufer,strlen(bufer),0);

int sockfd,n;
...
send(sockfd,buff,strlen(buff),0);