Gnu e?grep 1.6

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+This README documents GNU e?grep version 1.6.  All bugs reported for
+previous versions have been fixed.
+
+See the file INSTALL for compilation and installation instructions.
+
+Send bug reports to bug-gnu-utils@prep.ai.mit.edu.
+
+GNU e?grep is provided "as is" with no warranty.  The exact terms
+under which you may use and (re)distribute this program are detailed
+in the GNU General Public License, in the file COPYING.
+
+GNU e?grep is based on a fast lazy-state deterministic matcher (about
+twice as fast as stock Unix egrep) hybridized with a Boyer-Moore-Gosper
+search for a fixed string that eliminates impossible text from being
+considered by the full regexp matcher without necessarily having to
+look at every character.  The result is typically many times faster
+than Unix grep or egrep.  (Regular expressions containing backreferencing
+may run more slowly, however.)
+
+GNU e?grep is brought to you by the efforts of several people:
+
+	Mike Haertel wrote the deterministic regexp code and the bulk
+	of the program.
+
+	James A. Woods is responsible for the hybridized search strategy
+	of using Boyer-Moore-Gosper fixed-string search as a filter
+	before calling the general regexp matcher.
+
+	Arthur David Olson contributed code that finds fixed strings for
+	the aforementioned BMG search for a large class of regexps.
+
+	Richard Stallman wrote the backtracking regexp matcher that is
+	used for \<digit> backreferences, as well as the getopt that
+	is provided for 4.2BSD sites.  The backtracking matcher was
+	originally written for GNU Emacs.
+
+	D. A. Gwyn wrote the C alloca emulation that is provided so
+	System V machines can run this program.  (Alloca is used only
+	by RMS' backtracking matcher, and then only rarely, so there
+	is no loss if your machine doesn't have a "real" alloca.)
+
+	Scott Anderson and Henry Spencer designed the regression tests
+	used in the "regress" script.
+
+	Paul Placeway wrote the manual page, based on this README.
+
+If you are interested in improving this program, you may wish to try
+any of the following:
+
+1.  Replace the fast search loop with a faster search loop.
+    There are several things that could be improved, the most notable
+    of which would be to calculate a minimal delta2 to use.
+
+2.  Make backreferencing \<digit> faster.  Right now, backreferencing is
+    handled by calling the Emacs backtracking matcher to verify the partial
+    match.  This is slow; if the DFA routines could handle backreferencing
+    themselves a speedup on the order of three to four times might occur
+    in those cases where the backtracking matcher is called to verify nearly
+    every line.  Also, some portability problems due to the inclusion of the
+    emacs matcher would be solved because it could then be eliminated.
+    Note that expressions with backreferencing are not true regular
+    expressions, and thus are not equivalent to any DFA.  So this is hard.
+
+3.  Handle POSIX style regexps.  I'm not sure if this could be called an
+    improvement; some of the things on regexps in the POSIX draft I have
+    seen are pretty sickening.  But it would be useful in the interests of
+    conforming to the standard.
+
+4.  Replace the main driver program grep.c with the much cleaner main driver
+    program used in GNU fgrep.