The web page is not working for me, but I figured out how to access it anyways.

I put the code:

  /F ARGUMENTS 0 get (r) file def
  ARGUMENTS length 1 gt {F ARGUMENTS 1 get cvi 175 mul setfileposition} if

After 6.567 seconds, the explanation comes:

> This code defines a PostScript function called "F" that takes an argument and sets it as the name of a file to be opened. Then, it checks if there is at least one more argument in "ARGUMENTS", the array where the function's arguments are stored. If so (i.e., if the length of ARGUMENTS is greater than 1), the code converts the second argument from string to integer with "cvi", multiplies it by 175 and sets the file position to that value.

It is almost right but not quite. It is a PostScript code (it gets that correct), but it does not define a function called F; it defines F to refer to the file that it just opened. ARGUMENTS is an array of the command-line arguments of the PostScript program (the ability for PostScript programs to take command-line arguments is a feature specific to Ghostscript, although even in a different PostScript interpreter you could just define ARGUMENTS yourself anyways), not the arguments of the function. The rest is correct. (Of course, the above code is not a complete program.)