This is the list of Interfaces provided by the NASTRAN Commands Repository. All Bulk Data entries are represented by IGenericCommand, except ADAPT, OUTPUT and OUTRCV which are represented by the IOptionsControlCommand. And, the case control section commands are represented by ICaseControlCommand.

IGenericCommand : public ICommand
{
    int ArgumentCount();
    string GetArgument(int index);
};

ICaseControlCommand : public ICommand
{
    string Text();
};

INastranOption
{
    string Name();
    string Value();
};

INastranOptionLine
{
    int OptionCount();
    INastranOption GetOption(int index);
};

IOptionsControlCommand : public ICommand
{
    int ArgumentCount();
    string GetArgument(int index);
    int OptionLineCount();
    INastranOptionLine GetOptionLine(int index);
}