{
wxCHECK_MSG( str, false, wxT("invalid parameter") );
wxCHECK_MSG( IsOpened(), false, wxT("can't read from closed file") );
wxCHECK_MSG( Length() >= 0, false, wxT("invalid length") );
{
wxCHECK_MSG( str, false, wxT("invalid parameter") );
wxCHECK_MSG( IsOpened(), false, wxT("can't read from closed file") );
wxCHECK_MSG( Length() >= 0, false, wxT("invalid length") );