gnuan prompts for input parameters when it is invoked. Input file is a gnuchess list file or a xboard game file or a PGN file.
gnuan is a modification of the gnuan program from Truman Collins (tcollins@pdx.mentor.com).
bd -- Print out the current board
depth n -- set depth to search
next -- find the next best move in this position.
top n -- find the best n moves (1<n<5) in each position.
quit -- quit
n -- where n is a number, go to move n. n must be forward from current position
var -- enter a variation from the stored line. Return from the variation will go back to the current posution. If you are in a variation you enter the moves and they are then evaluated.
rav -- return from a variation.
go -- advance 1 ply.
To emulate the old gnuan just type a number > number of moves at the command prompt. The moves will be examined til the end of the game.