#include <stdio.h>#include <stdlib.h>#include <sys/types.h>#include <sys/socket.h>#include <sys/stat.h>#include <sys/time.h>#include <assert.h>#include <fcntl.h>#include <netinet/in.h>#include <netdb.h>#include <assert.h>#include <sys/errno.h>#include <errno.h>#include <strings.h>#include <string.h>#include <netinet/in.h>#include <arpa/inet.h>#include <signal.h>#include <unistd.h>#define BACKLOG 20#define RECEIVE_BUFF_SIZE 1024*5int main( int argc , char ** argv ) {	int iSin_size;	int iSockfd;	int iRet = -1;		int iServerPort;	struct sockaddr_in server_addr;	struct sockaddr_in client_addr;	char * cLogin = "login :";	char * cPasswd = "passwd :";	char sLogin[50];	char sPasswd[50];	char * pLogin = "nxb";	char * pPasswd = "1234";	int iLogin = 1;	char sReceiveBuff[RECEIVE_BUFF_SIZE];	char sKeyBoardInput[RECEIVE_BUFF_SIZE];		char sPrintLogBuff[RECEIVE_BUFF_SIZE];	char pLogName[100];	if ( argc < 2 ) {		printf ( "Usage : %s parameter\n" , argv[0] );	}	iServerPort = atoi ( argv[1] );	snprintf ( pLogName , sizeof ( pLogName ) , "%s" , argv[2] );	iSockfd = socket ( AF_INET , SOCK_DGRAM , 0 );	if ( iSockfd == -1 ) {		printf ( "Socket Found error !\n" );		exit ( 1 );	}		printf ( "Socket Found Success !\n" );	server_addr.sin_family = AF_INET;	server_addr.sin_port = htons ( iServerPort );	server_addr.sin_addr.s_addr = htonl ( INADDR_ANY );		bzero ( & ( server_addr.sin_zero ) , 8 );	if ( bind ( iSockfd , ( struct sockaddr * )&server_addr , sizeof ( struct sockaddr ) ) == -1 ) {		printf ( "Bind Error !\n" );		exit ( 1 );	}	printf ( "Bind Success !\n" );	while ( 1 ) {		iSin_size = sizeof ( struct sockaddr );		memset ( sReceiveBuff , 0 , sizeof ( sReceiveBuff ) );		iRet = recvfrom ( iSockfd , sReceiveBuff , RECEIVE_BUFF_SIZE , 0 , ( struct sockaddr * ) &client_addr , &iSin_size );		if ( iRet == -1 ) {			printf ( "Receive Error !\n" );		}else if ( iRet == 0 ) {			printf ( "Client Closed !\n" );			close ( iSockfd );			break;		}else {			printf ( "Receive Message : %s\n" , sReceiveBuff );			memset ( sPrintLogBuff , 0 , sizeof ( sPrintLogBuff ) );			snprintf ( sPrintLogBuff , sizeof ( sPrintLogBuff ) , "Receive Message : %s\n" , sReceiveBuff );			iWriteLog ( pLogName , sPrintLogBuff );		}		printf ( "Send Message : " );		scanf ( "%s" , &sKeyBoardInput ); 		memset ( sPrintLogBuff , 0 , sizeof ( sPrintLogBuff ) );		snprintf ( sPrintLogBuff , sizeof ( sPrintLogBuff ) , "Send Message : %s\n" , sKeyBoardInput );		iWriteLog ( pLogName , sPrintLogBuff );		iRet = sendto ( iSockfd , sKeyBoardInput , strlen( sKeyBoardInput ) , 0 , ( struct sockaddr * ) &client_addr , iSin_size );		if ( iRet == -1 ) {			printf ( "Send Error !\n" );		}	}}int iWriteLog (char * pFileName, char * pLogBuff){	int iOpenfd;	int iWriteNum;	iOpenfd = open ( pFileName , O_APPEND|O_RDWR|O_CREAT , S_IRWXU );	iWriteNum = write (iOpenfd , pLogBuff , strlen ( pLogBuff ) );	return iWriteNum;}