What it is. In 1982 Kent Pitman (KMP) wrote a MacLisp program on MIT-MC, the AI Lab's PDP-10 running ITS, that dresses a restaurant guide up as the ARPANET's File Transfer Protocol. You don't fetch files; you open a connection to a restaurant. Its banner was FTP.127 (Food Transfer Protocol), it answered Bugs/Gripes to KMP@MIT-MC, and its commands are FTP's with the obvious substitutions:

• CONNECT to a site, DISCONNECT, STATUS to describe the connection.
• BITE sets the transfer size, SMALL, MEDIUM or LARGE, the way FTP sets byte size. Uno's has a different menu for each.
• MENU lists what the connected server offers. SITES lists the active network.
• NETWORK edits which servers are considered, with filters (TYPE, LOCATION, QUALITY in stars, NOT, ALL, NONE) that combine like a query: network set type chinese, then network add type pizza.
• TIME prints the time; restaurants that are closed answer "Host unavailable due to scheduled down."

The joke runs through every message: "Host not responding. Still trying...", "Attempt to open connection to server timed out.", "Warning: Site being debugged." The data is not a joke. Each of the 78 entries is a real Boston or Cambridge restaurant near MIT, with address, phone, subway stop, hours, cost, stars, notes ("Won't seat partial groups; latecomers can't join a seated group") and sometimes the whole menu: Mary Chung's, Joyce Chen's Small Eating Place, Legal Sea Foods, Toscanini's, the Middle East, Joe's Pizza Truck. The entries are dated from August 1977 to January 1985.

Mary Chung's was one of the AI Lab hackers' favorite restaurants: a Szechuan place on Mass Ave between Main Street and Central Square, a short walk from Tech Square, where late-night dinners of dun dun noodles, suan la chow show and Peking ravioli fed generations of MIT hackers. FTP gives it four stars, notes "Good dimsum," and carries its menu: try connect mary-chungs, then menu.

Where it ran. MIT-MC, one of the ITS machines at Tech Square, in 1982–85. The 1982 directory maps list Kent's source as KMP; FTP 94 and the data as KMP; FTPDAT 21, compiled and dumped as HUMOR; TS FTP within five minutes on 18 July 1982. The surviving binary is a later build, from BMT1;FTP 127. The command line is Kent's own completing reader, LIBDOC; COMRD, which other ITS programs used too: the INQUIR source plans "fancier search criteria ala KMP's food transfer protocol."

How it was restored. Only the executable survives, in PDP-10/its-vault; the source and the data file are lost.

1. Lars Brinkhoff's pdp10-its-disassembler reads it as an ITS PDUMP: a saved MacLisp that shares its pure pages with SYS: PURQIO, Lisp version 4132.
2. Plain strings finds nothing, since a PDP-10 word holds five 7-bit characters. Read that way, the text comes out interleaved, because MacLisp keeps a symbol's name as a linked list of words. Following those links gives back 1,015 whole strings: every command, help line and message.
3. Each restaurant is a Lisp symbol whose property list holds its fields. Walking the heap (symbols, fixnums, flonums for half hours, lists, dotted pairs for cost ranges) rebuilds all 78 entries as JSON. A fragment of the original data file, left in a buffer, has the Kabuki and Al Capone's entries as source; the rebuilt data matches them exactly.
4. The page above uses only what was recovered for its messages, and follows Kent's COMRD for the command line. A few things the binary can't tell us, such as the prompt and the help layout, are marked "guessed" in the code.

It is a parody of a protocol, a restaurant guide, and a piece of MIT history. It is also an early example of a program you talk to by completion and ?, the way TOPS-20 users expected.

More.

• Run it on its own page — the same program, full window.
• Analysis and archive request — what is missing (the source, FTPDAT) and the scoped request to MIT's Tapes of Tech Square for it.
• The files — the binary, its disassembly, the recovered strings, the extractor and the page.
• Kent Pitman — MacLisp, the Common Lisp condition system, and much of ITS's Lisp culture.
• PDP-7 and PIXIE live — the other machine restored in this database.