This section describes in detail how the interpreter at the core of sniffle works. To learn about other aspects of the WEBRTI.EXE program, read subroutine Main of module webrti.bas, provided in an appendix. It's under two pages of thoroughly commented code, and it should be clear to anyone who understands Visual Basic. It is beyond the scope of this document to explain the off-the-shelf components of sniffle, e.g. the WinHTTPD server. Refer to the appropriate documentation to learn more about them.
This section assumes a basic understanding of HTML, HTTPD servers, the WinHTTPD cgi-win interface, the RTI-815 I/O board, and the Tektronix 222 digital oscilloscope.
Caveat: in the Princeton Computer Science department, students in programming courses are taught never to trust a program's documentation. In real life, the code behind a project and the code's documentation quickly fall out of sync. It usually isn't long before the documentation becomes, in the words of Bjarne Storstrup, ``a fairy tale.'' Every reasonable effort has been made to ensure the accuracy of the report that you are now reading, but if you really want to understand how sniffle works, read the code. You have been warned.