added underscore in tID at solly's request.

lexer.c

@@ -114,7 +114,7 @@ TOKEN nexttok()
 			if( isalpha( c ) )
 			{
 				curtok = tID;
-				for( pos=0; isalpha(c) || isdigit(c); )
+				for( pos=0; isalpha(c)||isdigit(c)||c=='_'; )
 				{
 					if( pos<MAXIDSIZE-1 )
 						lexidval[pos++] = c;