[C++] vprašanja

#include <cstdlib>
#include <string>
#include <iostream>

char *Construct(char *Name = new char[30] , char *Text = new char[256])
{
    char *assistant;
    system("cls");
    assistant = "[";
    std::cout << assistant << std::endl;
    strcat(assistant, Name);   //zapre program
    std::cout << assistant << std::endl;
    strcat(assistant, "] ");
    std::cout << assistant << std::endl;
    strcat(assistant, Text);
    std::cout << assistant << std::endl;
    return assistant;
}

int main()
{
    char *Name = new char[30];
    char *SendText = new char[256];
    std::cout << "Your name : ";
    std::cin.getline(Name, 30, '\n');
	while(true)
	{
  		std::cout << "[" << Name << "] ";
		std::cin.getline(SendText, 256 , '\n');
		if(strcmp(SendText, "/exit") == 0)
			return 0;
		SendText = Construct(Name,SendText);
		delete[] SendText;
	}
	return 0;
}

#include <cstdlib>
#include <string>
#include <iostream>

int main()
{
    std::string Name;
    std::string Text;
    std::cout << "Your nick : ";
    std::cin >> Name;
    Name = "[" + Name + "] ";    
    system("CLS");
	while(true)
	{   
  		std::cout << Name;
		std::cin >> Text;
		if(Text == "/exit")
			return 0;
		Text = Name + Text;
        char* SendText = const_cast<char*> (Text.c_str());
        std::cout << SendText << std::endl;
	}
	return 0;
}

#pragma warning(disable:4786)
#include <cstdlib>
#include <cstring>
#include <iostream>

int main()
{
  std::string Name;
  std::string Text;
  std::cout << "Tvoj vzdevek : ";
  std::cin >> Name;
  Name = "[" + Name + "] ";    
  while(true)
  {  
    std::getline(std::cin,Text,'\n');
    if(Text == "/exit")
      return 0;
    if (Text == "/cls")
      system("CLS"); //pobrise zaslon v win in *nix
    std::cout << Name;
  }
  return 0;
}

#include <iostream>
#include <cstring>
#include <cstdlib>
#include <winsock.h>

int main(int argc, char *argv[])
{
 system("cls");
 system("color 0a");
 SOCKET client_sd;     /* Socket descriptor of client */
 SOCKET server_sd;     /* Socket descriptor of server */
 char ReadText[256];   /* Data received from client */
 unsigned short int port_number; /* Port number */
 int a1, a2, a3, a4;   /* Address numbers in xxx.xxx.xxx.xxx form */
 struct sockaddr_in server;  /* Information about the server */
 struct sockaddr_in client;  /* Information about the client */
 int client_length;    /* Length of the client information struct */
 WSADATA w;  /* Used for opening up Windows connection */
 char client_address[32]; /* Address of the client */
 
 std::string Name, Name_;
 std::string Text;
 
 /* Make sure there are three entries on the command line */
 if (argc != 4)
 {
  std::cout << "Usage: simpcli [server address] [port number] [nickname]" << std::endl;
  system("pause");
  exit(0);
 }
 
 /* Read the command line */
 if (sscanf(argv[1], "%d.%d.%d.%d", &a1, &a2, &a3, &a4) != 4)
 {
  std::cout << "Error reading address in xxx.xxx.xxx.xxx form." << std::cout;
  system("pause");
  exit(0);
 }
 
 if (sscanf(argv[2], "%u", &port_number) != 1)
 {
  std::cout <<  "Error reading port number." << std::endl;
  system("pause");
  exit(0);
 }
 
 if (sscanf(argv[3], "%s", &Name_) != 1)
 {
  std::cout <<  "Error reading nickname." << std::endl;
  system("pause");
  exit(0);
 }
 
 /* Open up the Windows connection. This is necessary before calling
 the other WinSock functions. */
 if (WSAStartup(0x0101, &w) != 0)
 {
  std::cout << "Could not open windows connection." << std::endl;
  exit(0);
 }
 
 /* Open up a TCP/IP socket. */
 server_sd = socket(AF_INET, SOCK_STREAM, 0);
 
 /* Make sure the socket was opened, and quit if not */
 if (server_sd == INVALID_SOCKET)
 {
  fprintf(stderr, "Could not create socket.\n");
  WSACleanup();
  exit(0);
 }
 
 /* Set up the information in the server information structs */
 
 /* Step 3a: Clear the memory in the server struct */
 memset((void *)&server, '\0', sizeof(struct sockaddr_in));
 
 /* Step 3b: Set the family of the server */
 server.sin_family = AF_INET;
 
 /* Step 3c: Set the port */
 server.sin_port = htons(port_number);
 
 /* Step 3d: Copy the server address into the struct */
 server.sin_addr.S_un.S_un_b.s_b1 = (unsigned char)a1;    
 server.sin_addr.S_un.S_un_b.s_b2 = (unsigned char)a2;
 server.sin_addr.S_un.S_un_b.s_b3 = (unsigned char)a3;
 server.sin_addr.S_un.S_un_b.s_b4 = (unsigned char)a4;
 
 
 /* Bind server address to socket */
 if (bind(server_sd, (struct sockaddr *)&server, sizeof(struct sockaddr_in)) == -1)
 {
  std::cout << "Could not bind address to socket." << std::endl;
  closesocket(server_sd);
  WSACleanup();
  exit(0);
 }
 
 /* Print out some information */
 std::cout << "Server running on " << argv[1] << std::endl;
 std::cout << "Press CTRL + C to terminate the server." << std::endl;
 
 /* Listen for connections */
 listen(server_sd, 3);
 
 /* Step 6a: Accept the client */
 client_length = (int)sizeof(struct sockaddr_in);
 if ((client_sd = accept(server_sd, (struct sockaddr *)&client, &client_length)) == -1)
 {
  std::cout << "Could not accept client." << std::endl;
  closesocket(server_sd);
  WSACleanup();
  exit(0);
 }
 
  /* Step 6b: Get the client's address */
  sprintf(client_address, "%d.%d.%d.%d", (unsigned char)client.sin_addr.S_un.S_un_b.s_b1, 
     (unsigned char)client.sin_addr.S_un.S_un_b.s_b2,
  (unsigned char)client.sin_addr.S_un.S_un_b.s_b3,
  (unsigned char)client.sin_addr.S_un.S_un_b.s_b4);
  std::cout << "Client accepted on " <<  argv[1] << std::endl 
   << "_________________________________________" << std::endl;
 
 /******************** STEP 6 *********************************/
 /* Loop and wait for client to connect */
 Name = argv[3];
 Name = "[" + Name + "] ";
 while(1)
 {
  /************** STEP 7 ***********************************/
  /* Get data from client until there's no more to get */
  recv(client_sd, ReadText, 255, 0);
  std::cout << Text << std::endl;
 
  std::cout << Name;
  std::getline (std::cin,Text);
  Text = Name + Text;
  char* SendText = const_cast<char*> (Text.c_str());
  /* Send data */
  send(client_sd, SendText, (int)strlen(SendText) + 1, 0);
 }
   closesocket(client_sd); /* Close client socket */
 
 return 0;
 }
 
 
 
 Koda za client
 
 #include <iostream>
 #include <cstring>
 #include <cstring>
 #include <cstdlib>
 #include <winsock.h>
 
 int main(int argc, char *argv[])
 {
 system("cls");
 system("color 0a");
 SOCKET sd;  /* The socket descriptor */
 int a1, a2, a3, a4;   /* The four numbers of the address in xxx.xxx.xxx.xxx form */
 WSADATA w;  /* Used to open the Windows connection */
 struct sockaddr_in server;  /* The server information */
 unsigned short int port_number;  /* The port to use */
 char ReadText[256];   /* The response from the server */
 
 std::string Name, Name_;
 std::string Text;
 
 /* Make sure there are three entries on the command line */
 if (argc != 4)
 {
  std::cout << "Usage: simpcli [server address] [port number] [nickname]" 
    << std::endl;
  system("pause");
  exit(0);
 }
 
 /* Read the command line */
 if (sscanf(argv[1], "%d.%d.%d.%d", &a1, &a2, &a3, &a4) != 4)
 {
  std::cout << "Error reading address in xxx.xxx.xxx.xxx form." << std::cout;
  system("pause");
  exit(0);
 }
 
 if (sscanf(argv[2], "%u", &port_number) != 1)
 {
  std::cout <<  "Error reading port number." << std::endl;
  system("pause");
  exit(0);
 }
 
 if (sscanf(argv[3], "%s", &Name_) != 1)
 {
  std::cout <<  "Error reading nickname." << std::endl;
  system("pause");
  exit(0);
 }
 
 /* Open up the Windows connection. This is necessary before calling
 the other WinSock functions. */
 if (WSAStartup(0x0101, &w) != 0)
 {
  std::cout << "Could not open windows connection." << std::endl;
  system("pause");
  exit(0);
 }
 
 /* Open up a TCP/IP socket. */
 sd = socket(AF_INET, SOCK_STREAM, 0);
 
 /* Make sure the socket was opened, and quit if not */
 if (sd == INVALID_SOCKET)
 {
  std::cout << "Could not create socket." << std::endl;
  system("pause");
 WSACleanup();
 
  exit(0);
 }
 
 /* Set up the information in the server information structs */
 /* Step 3a: Clear the memory in the server struct */
 memset((void *)&server, '\0', sizeof(struct sockaddr_in));
 
 /* Step 3b: Set the family of the server */
 server.sin_family = AF_INET;
 
 /* Step 3c: Set the port */
 server.sin_port = htons(port_number);
 
 /* Step 3d: Copy the server address into the struct */
 server.sin_addr.S_un.S_un_b.s_b1 = (unsigned char)a1;    
 server.sin_addr.S_un.S_un_b.s_b2 = (unsigned char)a2;
 server.sin_addr.S_un.S_un_b.s_b3 = (unsigned char)a3;
 server.sin_addr.S_un.S_un_b.s_b4 = (unsigned char)a4;
 
 /* Connect to the remote server */
 if (connect(sd, (struct sockaddr *)&server, sizeof(struct sockaddr_in)) != 0)
 {
  std::cout << "Could not connect to address " << argv[1] << " on port" 
    << port_number << std::endl;
  closesocket(sd);
  WSACleanup();
  system("pause");
  exit(0);
 }
 
 /* We are now connected to the server, so we can send and receive data
 according to the protocol established */
 
 /*************** STEP 5 ***************************************/
 /* Transmit data to server */
  std::cout << "_________________________________________" << std::endl;
  Name = argv[3];
  Name = "[" + Name + "] ";
 do
 {
   std::cout << Name;
   std::getline (std::cin,Text);
   Text = Name + Text;
   /* Send data */
   send(sd, Text.c_str(), Text.size() + 1, 0);
 
 /*************** STEP 6 ***************************************/
 /* Receive data back from server */
   recv(sd, ReadText, 255, 0);
   std::cout << ReadText << std::endl;
 }
 while(1);
 
 /**************** STEP 7 ************************************/
 /* Close the socket */
 closesocket(sd);
 
 
 /***************** STEP 8 *************************************/
 /* Close the Windows connection */
 WSACleanup();
 
 return 0;
}