Word guessing game

Question

A program should take an input on stdin, and guess what a word might be. It should run as a session. One example session is shown below. Characters are fed to it, with a * for a letter not revealed; it should remember letters already revealed. It shows possible words in a list if the total number words found is less than 20, otherwise it shows the count of words.

I recommend /usr/share/dict/words on any Linux/Unix for the list of words, or your favourite word list on other platforms.

Example session (yours may vary):

>>> *****
6697 matches
>>> G****
312 matches
>>> *u***
Trying Gu***
35 matches
>>> Gu**s
Gus's
Guy's
guess
gulfs
gulls
gulps
gum's
gun's
gurus
gusts
gut's
guy's
12 matches
>>> **e**
Trying Gue*s
Is it "guess"?

Answer 1

Bash (171)

#!/bin/bash
s=`cat /dev/stdin | sed 's/\*/\./g'`;o=`cat /usr/share/dict/words | grep -x $s`;w=`echo "$o" | wc -l`;if [ $w -lt '20' ]; then echo "$o";fi;echo "$w match(es)"

Answer 2

Perl, 170 chars

open W,'</usr/share/dict/words';@D=<W>;
while(<>){@W=split//,$w;$w&&s/\*/$W[$-[0]]/ge;y/*/./;$w=$_;
($r=@R=grep/^$w$/i,@D)<20&&map{print}@R;print$r." matches\n";$r<2&&last}

Added (not counted) newlines for clarity.

Answer 3

PHP, 302

<?system('stty -icanon');$i=0;$s=explode(PHP_EOL,file_get_contents('/usr/share/dict/words'));while(1){$q.=fread(STDIN,1);system('clear');$x=0;$a='';$i++;for($j=0;$j<count($s);$j++){if(!strncasecmp($q,$s[$j],$i)){$x++;$a.="\n$s[$j]";}}echo str_pad($q,20,'*');echo$x<=20?"\n$a":'';echo"\n$x matches\n";}