// на С++

#define EXPORT extern "C" __declspec(dllexport)
#define PBCALL __stdcall

EXPORT size_t PBCALL calcTotalSize(TCHAR* arr[], size_t arraySize)
{
  size_t totalSize =  0 ;
  for (size_t i =  0 ; i < arraySize; i ++) {
    totalSize += _tcslen(arr[i]);
  }
  return totalSize;
}

EXPORT void PBCALL copyArr(TCHAR* arr[], size_t arraySize, TCHAR res[])
{
  size_t pos =  0 ;
  for (size_t i =  0 ; i < arraySize; i ++, pos += len) {
    size_t len = _tcslen(arr[i]);
    memcpy(&res[pos], arr[i], len * sizeof(TCHAR));
  }
}

// В PB
Function ulong calcTotalSize(readonly string arr[], ulong size) alias for "_calcTotalSize@8" library "utils.dll"
Subroutine copyArr(readonly string arr[], ulong size, ref string res) alias for "_copyArr@12" library "utils.dll"

ll_tot_size = calcTotalSize(ls_arr[], UpperBound(ls_arr[]));
ls_res = space(ll_tot_size) 
copyArr(ls_arr[], UpperBound(ls_arr[]), ref ls_res)

ls_arr = lds.object.text_col[ 1 , lds.RowCount()]
ll_tot_size = calcTotalSize(ls_arr[], UpperBound(ls_arr[]));
ls_res = space(ll_tot_size) 
copyArr(ls_arr[], UpperBound(ls_arr[]), ref ls_res)