Cryptonomicon

He got the idea for one of these when he was paging through the Cryptonomiconand discovered an appendix that contained a listing of the Morse code. Randy knew Morse code when he was a Boy Scout, and learned it again a few years ago when he was studying for a ham radio license, and it doesn't take him long to refresh his memory. And neither does it take him very long to write a little bit of code that turns his computer's space bar into a Morse code key, so that he can talk to the machine by whacking out dots and dashes with his thumb. This might look a little conspicuous, if not for the fact that Randy spends half of his time reading text files in little windows on the screen, and the way you page through a text file in most UNIX systems is by whacking the space bar. All he has to do is whack it in a particular rhythm, a detail he's relying on the surveillance guys to miss. The results all go into a buffer that is never displayed on the screen, and get written out to files with completely meaningless names. So, for example, Randy can whack out the following rhythm on his spacebar while pretending to read a lengthy section of the Cryptonomicon:

dash dot dot dot (pause) dot dot dash (pause) dash dot (pause) dash dot dot (pause) dash dash dash (pause) dash dot dash

which ought to spell out BUNDOK. He doesn't want to open the resulting file on screen, but later, while he's in the middle of a long series of other cryptic commands he can type

grep ndo (meaningless file name) > (another meaningless file name)

and grep will search through the first-named file to see if it contains the string "ndo" and put the results into the second-named file, which he can then check quite a bit later. He can also do "grep bun" and "grep dok" and if the results of all of these greps are true then he can be pretty confident that he has successfully coded the sequence "BUNDOK" into that one file. In the same way he can code "COORDINATES" into some other file and "LATITUDE" into another, and various numbers into others, and finally by using another command called "cat" he can slowly combine these one-word files into longer ones. All of these demands the same ridiculous patience as, say, tunneling out of a prison with a teaspoon, or sawing through iron bars with a nail file. But there comes a point, after he's spent about a month in jail, when suddenly he's able to make a window appear on the screen that contains the following message:

COORDINATES OF PRIMARY STORAGE LOCATIONS

SITE BUNDOK: LATITUDE NORTH FOURTEEN DEGREES THIRTY-TWO MINUTES . . . LONGITUDE. EAST ONE TWO ZERO DEGREES FIFTY SIX MINUTES .

SITE MAKATI: (etc.)

SITE ELDORADO: (etc.)

All of which is total bullshit that he just made up. The coordinates given for the Makati site are those of a luxury hotel in Manila, sited at a major intersection that used to be the site of a Nipponese military airbase. Randy happens to have these numbers in his computer because he took them down during his very early days in Manila, when he was doing the GPS survey work for siting Epiphyte's antennas. The coordinates given for SITE ELDORADO are simply the location of the pile of gold bars that he and Doug Shaftoe went to examine, plus a small random error factor. And those given for SITE BUNDOK are the real coordinates of Golgotha plus a couple of random error factors that should have Wing digging a deep hole in the ground about twenty kilometers away from the real site.

How does Randy know that there is a site called Golgotha, and how does he know its real coordinates? His computer told him using Morse code. Computer keyboards have LEDs on them that are essentially kind of useless: one to tell you when NUM LOCK is on, one for CAPS LOCK, and a third one whose purpose Randy can't even remember. And for no reason other than the general belief that every aspect of a computer should be under the control of hackers, someone, some where, wrote some library routines called XLEDS that make it possible for programmers to turn these things on and off at will. And for a month, Randy's been writing a little program that makes use of these routines to output the contents of a text file in Morse code, by flashing one of those LEDs. And while all kinds of useless crap has been scrolling across the screen of his computer as camouflage, Randy's been hunched over gazing into the subliminal channel of that blinking LED, reading the contents of the decrypted Arethusa intercepts. One of which says:

THE PRIMARY IS CODE NAMED GOLGOTHA. COORDINATES OF THE MAIN DRIFT ARE AS FOLLOWS: LATITUDE NORTH (etc.)

Chapter 91 THE BASEMENT