Send message by socket in C blocks

I need to send data packets in blocks through a socket . I have a pointer of uchar with the complete message, and a variable of type int with the length of it.

The connection of the socket I have already done perfectly, I just need a help on how to achieve sending the message by blocks of 1024 since I was testing with several examples and with none I could get it.

Something like that is what I'm trying to solve:

BOOL enviarMensaje( UCHAR *sSndData, UINT16 ulSndDataLen)
{

   #define SEND_MAX_SIZE       1024   
   int handle=-1;
   short retVal =-1 ;
   int totalEnviados=0;

   handle=CrearSocket(sTCPAddress,ulTCPPort);
   timeout.tv_sec = 2; //segundos
   timeout.tv_usec = 100; //microsegundos
   setsockopt(handle,SOL_SOCKET,SO_RCVTIMEO,(char*)&timeout,sizeof(timeout));

   timeout.tv_sec = 2;
   timeout.tv_usec = 100;
   setsockopt(handle, SOL_SOCKET,SO_PKTRCVTIMEO,(char*)&timeout,sizeof(timeout));   

   if(handle >=0)
   {
      while(totalEnviados<ulSndDataLen){
         retVal = send(handle,sSndData,SEND_MAX_SIZE,0);
         totalEnviados+= retVal;
       }
       closesocket(handle);
   }
}