TCP协议的问题

   
Server端接收到Client端信息后不会返回给Client端

// TCPEchoServer.cpp : 定义控制台应用程序的入口点。
//

#include "stdafx.h"
#include <Windows.h>
#include <WinSock2.h>
#include <strsafe.h>

#pragma comment(lib, "Ws2_32.lib")

#define GRS_ALLOC(sz) HeapAlloc(GetProcessHeap(), 0 ,sz)
#define GRS_CALLOC(sz) HeapAlloc(GetProcessHeap(), HEAP_ZERO_MEMORY, sz)
#define GRS_CREALLOC(p, sz) HeapReAlloc(GetProcessHeap(), HEAP_ZERO_MEMORY, p, sz)
#define GRS_SAFEFREE(p) if(NULL != p){HeapFree(GetProcessHeap(), 0, p); p = NULL;}

#define GRS_USEPRINTF() TCHAR pBuf[1024] = {}; char pBufA[1024] = {};
#define GRS_PRINTF(...)
 StringCchPrintf(pBuf, 1024, __VA_ARGS__);
 WriteConsole(GetStdHandle(STD_OUTPUT_HANDLE), pBuf, lstrlen(pBuf), NULL, NULL);
#define GRS_PRINTFA(...)
 StringCchPrintfA(pBufA, 1024, __VA_ARGS__);
 WriteConsoleA(GetStdHandle(STD_OUTPUT_HANDLE), pBufA, lstrlenA(pBufA), NULL, NULL);

#define SOCK_VERH 2
#define SOCK_VERL 2
#define GRS_SERVER_PORT 5634
int _tmain(int argc, _TCHAR* argv[])
{
 GRS_USEPRINTF();
 WORD wVer = MAKEWORD(SOCK_VERH, SOCK_VERL);
 WSADATA wd;
 int err = ::WSAStartup(wVer, &wd); //因为多个WinSock版本库可能共存于一个系统，所以应用程序必须明确指定加载合适的WinSock版本库，这个过程称为WinSock初始化，一般用WSAStartup
 //高字节副版本号，低字节主版本号
 if(0 != err)
 {
  GRS_PRINTF(_T("无法初始化Scoket2环境，错误码为：%d! "), WSAGetLastError());
  return 1;
 }
 if(LOBYTE(wd.wVersion) != SOCK_VERH || HIBYTE(wd.wVersion) != SOCK_VERL)
 {
  GRS_PRINTF(_T("无法初始化%d.%d版本环境! "), SOCK_VERH, SOCK_VERL);
  ::WSACleanup();
  return 2;
 }
 GRS_PRINTF(_T("WinSock库初始化成功！ 当前系统中支持最高的WinSock版本为%d.%d 当前应用程序使用的WinSock版本为%d.%d "),
  LOBYTE(wd.wHighVersion), HIBYTE(wd.wHighVersion),
  LOBYTE(wd.wVersion), HIBYTE(wd.wVersion));

 SOCKET skServer = socket(AF_INET, SOCK_STREAM, IPPROTO_TCP);
 SOCKET skClient = INVALID_SOCKET;
 SOCKADDR_IN saClient = {};
 int isaLen = sizeof(SOCKADDR_IN);
 VOID* pskBuf = NULL;
 VOID* pskBufTmp = NULL;
 int iBufLen = 1024;
 int iBufLenTmp = 0;
 int iRecv = 0;

 SOCKADDR_IN sa = {AF_INET};
 sa.sin_addr.s_addr = htonl(INADDR_ANY);
 sa.sin_port = htons(GRS_SERVER_PORT);

 if(0 != bind(skServer, (SOCKADDR*)&sa, sizeof(SOCKADDR_IN)))
 {
  GRS_PRINTF(_T("绑定到指定端口出错! "));
  goto CLEAN_UP;
 }
 if(0 != listen(skServer, SOMAXCONN))
 {
  GRS_PRINTF(_T("SOCKET进入监听模式出错! "));
  goto CLEAN_UP;
 }
 while(INVALID_SOCKET != (skClient=accept(skServer, (SOCKADDR*)&saClient, &isaLen)))
 {
  GRS_PRINTFA("客户端[%s : %u]连接进来了..... ", inet_ntoa(saClient.sin_addr), ntohs(saClient.sin_port));
  GRS_PRINTF(_T(" 开始接受客户端数据...... "));
  pskBuf = GRS_CALLOC(iBufLen);
  pskBufTmp = pskBuf;
  do
  {
   iRecv = recv(skClient, (char*)pskBufTmp, iBufLen-iBufLenTmp, 0);
   if(SOCKET_ERROR == iRecv || 0 == iRecv)
   {
    break;
   }
   if(iRecv >= (iBufLen - iBufLenTmp))
   {
    iBufLenTmp = iBufLen;
    iBufLen += 1024;
    pskBuf = GRS_CREALLOC(pskBuf, iBufLen);
    pskBufTmp = (void*)((BYTE*)pskBuf + iBufLenTmp);
    continue;
   }
  }
  while (1);
  
  if(SOCKET_ERROR != iRecv && 0 != iRecv)
  {
   GRS_PRINTF(_T(" 接收客户端数据成功，开始返回...... "));
   send(skClient, (const char*)pskBuf, iBufLen, 0);
  }
  else
  {
   GRS_PRINTF(_T(" 接收客户端数据失败，关闭连接...... "));
  }

  GRS_SAFEFREE(pskBuf);
  pskBufTmp = NULL;
  iBufLenTmp = 0;
  iBufLen = 1024;

  shutdown(skClient, SD_BOTH);
  closesocket(skClient);
 }

CLEAN_UP:
 _tsystem(_T("PASUE"));
 if(INVALID_SOCKET != skServer)
 {
  closesocket(skServer);
 }
 ::WSACleanup();

 return 0;
}               //Server端的代码

// TCPEchoClient.cpp : 定义控制台应用程序的入口点。
//

#include "stdafx.h"
#include <Windows.h>
#include <strsafe.h>
#include <WinSock2.h>

#pragma comment(lib, "Ws2_32.lib")

#define GRS_ALLOC(sz) HeapAlloc(GetProcessHeap(), 0 ,sz)
#define GRS_CALLOC(sz) HeapAlloc(GetProcessheap(), HEAP_ZERO_MEMORY, sz)
#define GRS_CREALLOC(p, sz) HeapReAlloc(GetProcessHeap(), HEAP_ZERO_MEMORY, p, sz)
#define GRS_SAFEFREE(p) if(NULL != p){HeapFree(GetProcessHeap(), 0, p); p = NULL;}

#define GRS_USEPRINTF() TCHAR pBuf[1024] = {}; char pBufA[1024] = {};
#define GRS_PRINTF(...)
 StringCchPrintf(pBuf, 1024, __VA_ARGS__);
 WriteConsole(GetStdHandle(STD_OUTPUT_HANDLE), pBuf, lstrlen(pBuf), NULL, NULL);
#define GRS_PRINTFA(...)
 StringCchPrintfA(pBufA, 1024, __VA_ARGS__);
 WriteConsoleA(GetStdHandle(STD_OUTPUT_HANDLE), pBufA, lstrlenA(pBufA), NULL, NULL);

#define SOCK_VERH 2
#define SOCK_VERL 2
#define GRS_SERVER_PORT 5634

int _tmain(int argc, _TCHAR* argv[])
{
 GRS_USEPRINTF();
 WORD wVer = MAKEWORD(SOCK_VERH, SOCK_VERL);
 WSADATA wd;
 int err = ::WSAStartup(wVer, &wd); //因为多个WinSock版本库可能共存于一个系统，所以应用程序必须明确指定加载合适的WinSock版本库，这个过程称为WinSock初始化，一般用WSAStartup
 //高字节副版本号，低字节主版本号
 if(0 != err)
 {
  GRS_PRINTF(_T("无法初始化Scoket2环境，错误码为：%d! "), WSAGetLastError());
  return 1;
 }
 if(LOBYTE(wd.wVersion) != SOCK_VERH || HIBYTE(wd.wVersion) != SOCK_VERL)
 {
  GRS_PRINTF(_T("无法初始化%d.%d版本环境! "), SOCK_VERH, SOCK_VERL);
  ::WSACleanup();
  return 2;
 }
 GRS_PRINTF(_T("WinSock库初始化成功！ 当前系统中支持最高的WinSock版本为%d.%d 当前应用程序使用的WinSock版本为%d.%d "),
  LOBYTE(wd.wHighVersion), HIBYTE(wd.wHighVersion),
  LOBYTE(wd.wVersion), HIBYTE(wd.wVersion));

 SOCKET skClient = socket(AF_INET, SOCK_STREAM, IPPROTO_IP);
 SOCKADDR_IN sa = {AF_INET};
 sa.sin_addr.s_addr = inet_addr("127.0.0.1");
 sa.sin_port = htons(GRS_SERVER_PORT);
 WCHAR pszSendMsg[] = _T("Hello Internetssssssssssssssssssssssssss!");
 size_t szLen = 0;
 StringCchLength(pszSendMsg, 30, &szLen);
 WCHAR pszRecvBuf[1024] = {};
 if(0 != connect(skClient, (SOCKADDR*)&sa, sizeof(SOCKADDR_IN)))
 {
  GRS_PRINTF(_T("连接服务器出错...... "));
  goto CLEAN_UP;
 }
 send(skClient, (char*)pszSendMsg, szLen * sizeof(WCHAR), 0);
 recv(skClient, (char*)pszRecvBuf, 1024 * sizeof(WCHAR), 0);
 GRS_PRINTF(_T("ECHO:%s "), pszRecvBuf);

CLEAN_UP:
 if(INVALID_SOCKET != skClient)
 {
  shutdown(skClient, SD_BOTH);
  closesocket(skClient);
 }
 _tsystem(_T("PASUE"));
 ::WSACleanup();
 return 0;
}  //Client端的代码

Server端接收到Client端信息后不会返回给Client端，