recv接收数据不完整? 但wireshark抓包看到的数据是和服务端发出来的一致的

//客户端代码

DWORD WINAPI TcpRecvProc(void *pVoid)

{

	struct timeval tv = {0, 300*1000};

	fd_set rfds;

	char *buf = new char[MAX_VIDEO_FRAME_LEN];



	int cnt=0;

	while (g_RunThread)

	{

		FD_ZERO(&rfds);

		FD_SET(g_fd, &rfds);



		int ret = select((int)g_fd+1, &rfds, NULL, NULL, &tv);

		if (GetLastError()!=0)

			TRACE("GetLastError=%d\n", GetLastError());  //未输出错误

		if (ret<0)

			Sleep(100);

		else if (ret==0)

			Sleep(100);

		else

		{

			int n = recv(g_fd, buf, MAX_VIDEO_FRAME_LEN/4, 0);			

			if (n<=0)

			{

				if (GetLastError()!=0)

					TRACE("GetLastError=%d\n", GetLastError());//未输出错误

				continue;

			}	

			cnt+=n;

			TRACE("%d\n", cnt);



                        //一些业务处理代码 ...

                 }

}

//服务端输出
write errno=104, n=147533, fd=9, cmd=80,subcmd=80
write errno=104, n=116775, fd=9, cmd=80,subcmd=80
write errno=104, n=138693, fd=9, cmd=80,subcmd=80
write errno=104, n=144560, fd=9, cmd=80,subcmd=80
write errno=104, n=130876, fd=9, cmd=80,subcmd=80
write errno=104, n=126041, fd=9, cmd=80,subcmd=80
write errno=104, n=54170, fd=9, cmd=80,subcmd=80
write errno=104, n=21303, fd=9, cmd=80,subcmd=80
write errno=104, n=12842, fd=9, cmd=80,subcmd=80
write errno=104, n=11703, fd=9, cmd=80,subcmd=80
//wireshark的FollowTcpStream显示Entire conversation 904496，和服务端输出累加一致，不知道客户端为什么收不全？