===================================================================
RCS file: /cvsrepo/anoncvs/cvs/src/usr.bin/diff/diff.1,v
retrieving revision 1.27
retrieving revision 1.28
diff -u -r1.27 -r1.28
--- src/usr.bin/diff/diff.1	2004/12/09 18:56:10	1.27
+++ src/usr.bin/diff/diff.1	2005/01/06 00:28:53	1.28
@@ -1,4 +1,4 @@
-.\" $OpenBSD: diff.1,v 1.27 2004/12/09 18:56:10 millert Exp $
+.\" $OpenBSD: diff.1,v 1.28 2005/01/06 00:28:53 jmc Exp $
 .\"
 .\" Copyright (c) 1980, 1990, 1993
 .\"	The Regents of the University of California.  All rights reserved.
@@ -186,7 +186,16 @@
 .Bl -tag -width Ds
 .It Fl a
 Treat all files as
-.Tn ASCII .
+.Tn ASCII
+text.
+Normally
+.Nm
+will simply print
+.Dq Binary files ... differ
+if files contain binary characters.
+Use of this option forces
+.Nm
+to produce a diff.
 .It Fl b
 Causes trailing blanks (spaces and tabs) to be ignored, and other
 strings of blanks to compare equal.