(ediff)Introduction

Introduction
************

   Ediff provides a convenient way for simultaneous browsing through
the differences between a pair (or a triple) of files or buffers.  The
files being compared, file-A, file-B, and file-C (if applicable) are
shown in separate windows (side by side, one above the another, or in
separate frames), and the differences are highlighted as you step
through them.  You can also copy difference regions from one buffer to
another (and recover old differences if you change your mind).

   Another powerful feature is the ability to merge a pair of files
into a third buffer. Merging with an ancestor file is also supported.
Furthermore, Ediff is equipped with directory-level capabilities that
allow the user to conveniently launch browsing or merging sessions on
groups of files in two (or three) different directories.

   In addition, Ediff can apply a patch to a file and then let you step
though both files, the patched and the original one, simultaneously,
difference-by-difference.  You can even apply a patch right out of a
mail buffer, i.e., patches received by mail don't even have to be
saved.  Since Ediff lets you copy differences between buffers, you can,
in effect, apply patches selectively (i.e., you can copy a difference
region from `file_orig' to `file', thereby undoing any particular patch
that you don't like).

   Unfortunately, Ediff still doesn't understand multi-file
patches--this requires further work (volunteers needed!).

   Ediff is aware of version control, which lets you compare files with
their older versions. Ediff also works with remote and compressed
files, automatically ftp'ing them over and uncompressing them.  Note:
Remote and Compressed Files, for details.

   This package builds upon ideas borrowed from Emerge and several
Ediff's functions are adaptations from Emerge.  Although Ediff subsumes
Emerge, much of the functionality of Ediff is influenced by Emerge.
The architecture and the interface are, of course, drastically
different.