Add configure flag to allow libedit to be preferred over GNU readline:

   --with-libedit-preferred  prefer BSD Libedit over GNU Readline

config/programs.m4

-# $PostgreSQL: pgsql/config/programs.m4,v 1.18 2004/12/02 20:04:19 tgl Exp $
+# $PostgreSQL: pgsql/config/programs.m4,v 1.19 2005/12/04 03:52:28 momjian Exp $
 
 
 # PGAC_PATH_FLEX
@@ -78,12 +78,16 @@ AC_SUBST(FLEXFLAGS)
 
 AC_DEFUN([PGAC_CHECK_READLINE],
 [AC_REQUIRE([AC_CANONICAL_HOST])
-AC_MSG_CHECKING([for readline])
 
 AC_CACHE_VAL([pgac_cv_check_readline],
 [pgac_cv_check_readline=no
 pgac_save_LIBS=$LIBS
-for pgac_rllib in -lreadline -ledit ; do
+if test x"$with_libedit_preferred" != x"yes"
+then	READLINE_ORDER="-lreadline -ledit"
+else	READLINE_ORDER="-ledit -lreadline"
+fi
+for pgac_rllib in $READLINE_ORDER ; do
+  AC_MSG_CHECKING([for ${pgac_rllib}])
   for pgac_lib in "" " -ltermcap" " -lncurses" " -lcurses" ; do
     LIBS="${pgac_rllib}${pgac_lib} $pgac_save_LIBS"
     AC_TRY_LINK_FUNC([readline], [[
@@ -98,20 +102,25 @@ for pgac_rllib in -lreadline -ledit ; do
       esac
 
       pgac_cv_check_readline="${pgac_rllib}${pgac_lib}"
-      break 2
+      break
     ]])
   done
+  if test "$pgac_cv_check_readline" != no ; then
+    AC_MSG_RESULT([yes ($pgac_cv_check_readline)])
+    break
+  else
+    AC_MSG_RESULT(no)
+  fi
 done
 LIBS=$pgac_save_LIBS
 ])[]dnl AC_CACHE_VAL
 
 if test "$pgac_cv_check_readline" != no ; then
-  AC_DEFINE(HAVE_LIBREADLINE, 1, [Define if you have a function readline library])
   LIBS="$pgac_cv_check_readline $LIBS"
-  AC_MSG_RESULT([yes ($pgac_cv_check_readline)])
-else
-  AC_MSG_RESULT(no)
-fi])# PGAC_CHECK_READLINE
+  AC_DEFINE(HAVE_LIBREADLINE, 1, [Define if you have a function readline library])
+fi
+
+])# PGAC_CHECK_READLINE
 
 
 

configure

@@ -890,7 +890,8 @@ Optional Packages:
   --with-pam              build with PAM support
   --with-bonjour          build with Bonjour support
   --with-openssl          build with OpenSSL support
-  --without-readline      do not use Readline
+  --with-libedit-preferred  prefer BSD Libedit over GNU Readline
+  --without-readline      do not use GNU Readline / BSD Libedit line editing
   --without-zlib          do not use Zlib
   --with-gnu-ld           assume the C compiler uses GNU ld [default=no]
 
@@ -3771,6 +3772,37 @@ echo "${ECHO_T}$with_openssl" >&6
 
 
 
+#
+# Prefer libedit
+#
+
+
+
+# Check whether --with-libedit-preferred or --without-libedit-preferred was given.
+if test "${with_libedit_preferred+set}" = set; then
+  withval="$with_libedit_preferred"
+
+  case $withval in
+    yes)
+      :
+      ;;
+    no)
+      :
+      ;;
+    *)
+      { { echo "$as_me:$LINENO: error: no argument expected for --with-libedit-preferred option" >&5
+echo "$as_me: error: no argument expected for --with-libedit-preferred option" >&2;}
+   { (exit 1); exit 1; }; }
+      ;;
+  esac
+
+else
+  with_libedit_preferred=no
+
+fi;
+
+
+
 #
 # Readline
 #
@@ -6490,15 +6522,19 @@ fi
 
 if test "$with_readline" = yes; then
 
-echo "$as_me:$LINENO: checking for readline" >&5
-echo $ECHO_N "checking for readline... $ECHO_C" >&6
 
 if test "${pgac_cv_check_readline+set}" = set; then
   echo $ECHO_N "(cached) $ECHO_C" >&6
 else
   pgac_cv_check_readline=no
 pgac_save_LIBS=$LIBS
-for pgac_rllib in -lreadline -ledit ; do
+if test x"$with_libedit_preferred" != x"yes"
+then	READLINE_ORDER="-lreadline -ledit"
+else	READLINE_ORDER="-ledit -lreadline"
+fi
+for pgac_rllib in $READLINE_ORDER ; do
+  echo "$as_me:$LINENO: checking for ${pgac_rllib}" >&5
+echo $ECHO_N "checking for ${pgac_rllib}... $ECHO_C" >&6
   for pgac_lib in "" " -ltermcap" " -lncurses" " -lcurses" ; do
     LIBS="${pgac_rllib}${pgac_lib} $pgac_save_LIBS"
     cat >conftest.$ac_ext <<_ACEOF
@@ -6557,7 +6593,7 @@ if { (eval echo "$as_me:$LINENO: \"$ac_link\"") >&5
       esac
 
       pgac_cv_check_readline="${pgac_rllib}${pgac_lib}"
-      break 2
+      break
 
 else
   echo "$as_me: failed program was:" >&5
@@ -6567,24 +6603,29 @@ fi
 rm -f conftest.err conftest.$ac_objext \
       conftest$ac_exeext conftest.$ac_ext
   done
+  if test "$pgac_cv_check_readline" != no ; then
+    echo "$as_me:$LINENO: result: yes ($pgac_cv_check_readline)" >&5
+echo "${ECHO_T}yes ($pgac_cv_check_readline)" >&6
+    break
+  else
+    echo "$as_me:$LINENO: result: no" >&5
+echo "${ECHO_T}no" >&6
+  fi
 done
 LIBS=$pgac_save_LIBS
 
 fi
 
 if test "$pgac_cv_check_readline" != no ; then
+  LIBS="$pgac_cv_check_readline $LIBS"
 
 cat >>confdefs.h <<\_ACEOF
 #define HAVE_LIBREADLINE 1
 _ACEOF
 
-  LIBS="$pgac_cv_check_readline $LIBS"
-  echo "$as_me:$LINENO: result: yes ($pgac_cv_check_readline)" >&5
-echo "${ECHO_T}yes ($pgac_cv_check_readline)" >&6
-else
-  echo "$as_me:$LINENO: result: no" >&5
-echo "${ECHO_T}no" >&6
 fi
+
+
   if test x"$pgac_cv_check_readline" = x"no"; then
     { { echo "$as_me:$LINENO: error: readline library not found
 If you have readline already installed, see config.log for details on the

configure.in

 dnl Process this file with autoconf to produce a configure script.
-dnl $PostgreSQL: pgsql/configure.in,v 1.432 2005/11/05 16:42:01 tgl Exp $
+dnl $PostgreSQL: pgsql/configure.in,v 1.433 2005/12/04 03:52:24 momjian Exp $
 dnl
 dnl Developers, please strive to achieve this order:
 dnl
@@ -467,11 +467,18 @@ AC_MSG_RESULT([$with_openssl])
 AC_SUBST(with_openssl)
 
 
+#
+# Prefer libedit
+#
+PGAC_ARG_BOOL(with, libedit-preferred, no,
+              [  --with-libedit-preferred  prefer BSD Libedit over GNU Readline])
+
+
 #
 # Readline
 #
 PGAC_ARG_BOOL(with, readline, yes,
-              [  --without-readline      do not use Readline])
+              [  --without-readline      do not use GNU Readline / BSD Libedit line editing])
 # readline on MinGW has problems with backslashes in psql and other bugs.
 # This is particularly a problem with non-US code pages.
 # Therefore disable its use until we understand the cause. 2004-07-20

doc/src/sgml/installation.sgml

-<!-- $PostgreSQL: pgsql/doc/src/sgml/installation.sgml,v 1.249 2005/11/05 00:04:04 tgl Exp $ -->
+<!-- $PostgreSQL: pgsql/doc/src/sgml/installation.sgml,v 1.250 2005/12/04 03:52:29 momjian Exp $ -->
 
 <chapter id="installation">
  <title><![%standalone-include[<productname>PostgreSQL</>]]>
@@ -107,16 +107,20 @@ su - postgres
       </indexterm>
 
       The <acronym>GNU</> <productname>Readline</> library (for
-      comfortable line editing and command history retrieval) will be
-      used by default.  If you don't want to use it then you must
-      specify the <option>--without-readline</option> option for
-      <filename>configure</>.  (On <productname>NetBSD</productname>,
-      the <filename>libedit</filename> library is
-      <productname>Readline</productname>-compatible and is used if
-      <filename>libreadline</filename> is not found.)  If you are using
-      a package-based Linux distribution, be aware that you need both
-      the <literal>readline</> and <literal>readline-devel</> packages,
-      if those are separate in your distribution.
+      simple line editing and command history retrieval) is
+      used by default. If you don't want to use it then you must specify
+      the <option>--without-readline</option> option for
+      <filename>configure</>. As an alternative, you can often use the
+      BSD-licensed <filename>libedit</filename> library, originally
+      developed on <productname>NetBSD</productname>. The
+      <filename>libedit</filename> library is
+      GNU <productname>Readline</productname>-compatible and is used if
+      <filename>libreadline</filename> is not found, or if
+      <option>--with-libedit-preferred</option> is used as an 
+      option to <filename>configure</>. If you are using a package-based
+      Linux distribution, be aware that you need both the 
+      <literal>readline</> and <literal>readline-devel</> packages, if 
+      those are separate in your distribution.
      </para>
     </listitem>
 
@@ -857,6 +861,16 @@ su - postgres
        </listitem>
       </varlistentry>
 
+      <varlistentry>
+       <term><option>--with-libedit-preferred</option></term>
+       <listitem>
+        <para>
+         Favors the use of the BSD-licensed <application>libedit</> library
+         rather than GPL-licensed <application>Readline</>.
+        </para>
+       </listitem>
+      </varlistentry>
+
       <varlistentry>
        <term><option>--without-readline</option></term>
        <listitem>