- new applet diff. Rob Sullivan writes:

Here's my attempt at a mini diff applet - it's adapted from the code at
http://www.openbsd.org/cgi-bin/cvsweb/src/usr.bin/diff/, and only supports
unified diffs.

I've busyboxified everything to a reasonable degree, so I think the code is
suitable enough to be included, but there's still a fair bit of cleaning up
to be done.

coreutils/Config.in

@@ -109,6 +109,38 @@ config CONFIG_DF
 	  df reports the amount of disk space used and available
 	  on filesystems.
 
+config CONFIG_DIFF
+	bool "diff"
+	default n
+	help
+	  diff compares two files or directories and outputs the
+	  differences between them in a form that can be given to
+	  the patch command.
+
+config CONFIG_FEATURE_DIFF_BINARY
+	bool "  Enable checks for binary files"
+	default y
+	depends on CONFIG_DIFF
+	help
+	  This option enables support for checking for binary files
+	  before a comparison is carried out.
+
+config CONFIG_FEATURE_DIFF_DIR
+	bool "  Enable directory support"
+	default y
+	depends on CONFIG_DIFF
+	help
+	  This option enables support for directory and subdirectory
+	  comparison.
+
+config CONFIG_FEATURE_DIFF_MINIMAL
+	bool "  Enable -d option to find smaller sets of changes"
+	default n
+	depends on CONFIG_DIFF
+	help
+	  Enabling this option allows the use of -d to make diff
+	  try hard to find the smallest possible set of changes.
+
 config CONFIG_DIRNAME
 	bool "dirname"
 	default n