diff --git a/configure b/configure
index aadfee85..c2e1cc36 100755
--- a/configure
+++ b/configure
@@ -645,7 +645,6 @@ have_png
 have_libuvc
 have_lapack
 have_toon
-have_shared_ptr
 have_videodisplay
 XMKMF
 have_qtbuffer
@@ -4469,7 +4468,6 @@ minor=$cvd_minor
 
 
 
-
 ################################################################################
 #
 #Lists of  optional components
@@ -6796,80 +6794,6 @@ fi
 
 
 
-	if test "$with_shared_ptr" != no && test "$have_shared_ptr" != yes
-	then
-		if test "$with_shared_ptr" == ""
-		then
-			with_shared_ptr=yes
-		fi
-
-		save_LIBS="$LIBS"
-		save_CXXFLAGS="$CXXFLAGS"
-		a=
-
-	{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for shared_ptr" >&5
-$as_echo_n "checking for shared_ptr... " >&6; }
-	cat confdefs.h - <<_ACEOF >conftest.$ac_ext
-/* end confdefs.h.  */
-#include <memory>
-	int main(){std::shared_ptr<int> i; return  0;}
-_ACEOF
-if ac_fn_cxx_try_compile "$LINENO"; then :
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: yes" >&5
-$as_echo "yes" >&6; }
-else
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: no" >&5
-$as_echo "no" >&6; }; a=1
-fi
-rm -f core conftest.err conftest.$ac_objext conftest.$ac_ext
-
-	if test x$a == x1
-	then
-		a=0
-		{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for tr1::shared_ptr" >&5
-$as_echo_n "checking for tr1::shared_ptr... " >&6; }
-		cat confdefs.h - <<_ACEOF >conftest.$ac_ext
-/* end confdefs.h.  */
-#include <tr1/memory>
-		int main(){std::tr1::shared_ptr<int> i; return  0;}
-_ACEOF
-if ac_fn_cxx_try_compile "$LINENO"; then :
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: yes" >&5
-$as_echo "yes" >&6; }
-else
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: no" >&5
-$as_echo "no" >&6; }; a=1
-fi
-rm -f core conftest.err conftest.$ac_objext conftest.$ac_ext
-		$as_echo "#define CVD_INTERNAL_NEED_TR1 1" >>confdefs.h
-
-		dodginess_options="$dodginess_options tr1_shared_ptr"
-	fi
-
-
-		if test x$a == x
-		then
-			$as_echo "#define CVD_HAVE_SHARED_PTR 1" >>confdefs.h
-
-			have_shared_ptr=yes
-
-			options="$options shared_ptr"
-
-		else
-			LIBS="$save_LIBS"
-			CXXFLAGS="$save_CXXFLAGS"
-		fi
-	fi
-
-	if test "$have_shared_ptr" != yes
-	then
-		:
-
-	fi
-
-
-
-
 	if test "$with_toon" != no && test "$have_toon" != yes
 	then
 		if test "$with_toon" == ""
@@ -6897,32 +6821,6 @@ $as_echo "no" >&6; }; a=1
 fi
 rm -f core conftest.err conftest.$ac_objext conftest.$ac_ext
 
-	if test x$a = x1
-	then
-		{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for old TooN" >&5
-$as_echo_n "checking for old TooN... " >&6; }
-		cat confdefs.h - <<_ACEOF >conftest.$ac_ext
-/* end confdefs.h.  */
-#include <TooN/TooN.h>
-		int main(){TooN::Vector<2> v;return 0;}
-_ACEOF
-if ac_fn_cxx_try_compile "$LINENO"; then :
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: yes" >&5
-$as_echo "yes" >&6; }
-else
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: no" >&5
-$as_echo "no" >&6; }; a=2
-fi
-rm -f core conftest.err conftest.$ac_objext conftest.$ac_ext
-
-		if test x$a = x1
-		then
-			{ $as_echo "$as_me:${as_lineno-$LINENO}: WARNING: Your version of TooN is too old. You need version 2.0-beta3 or later." >&5
-$as_echo "$as_me: WARNING: Your version of TooN is too old. You need version 2.0-beta3 or later." >&2;}
-		fi
-		a=1
-	fi
-
 
 		if test x$a == x
 		then
@@ -7690,60 +7588,6 @@ else
   a=1
 fi
 
-	oldpng=0
-	{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for png_set_expand_gray_1_2_4_to_8 in -lpng" >&5
-$as_echo_n "checking for png_set_expand_gray_1_2_4_to_8 in -lpng... " >&6; }
-if ${ac_cv_lib_png_png_set_expand_gray_1_2_4_to_8+:} false; then :
-  $as_echo_n "(cached) " >&6
-else
-  ac_check_lib_save_LIBS=$LIBS
-LIBS="-lpng  $LIBS"
-cat confdefs.h - <<_ACEOF >conftest.$ac_ext
-/* end confdefs.h.  */
-
-/* Override any GCC internal prototype to avoid an error.
-   Use char because int might match the return type of a GCC
-   builtin and then its argument prototype would still apply.  */
-#ifdef __cplusplus
-extern "C"
-#endif
-char png_set_expand_gray_1_2_4_to_8 ();
-int
-main ()
-{
-return png_set_expand_gray_1_2_4_to_8 ();
-  ;
-  return 0;
-}
-_ACEOF
-if ac_fn_cxx_try_link "$LINENO"; then :
-  ac_cv_lib_png_png_set_expand_gray_1_2_4_to_8=yes
-else
-  ac_cv_lib_png_png_set_expand_gray_1_2_4_to_8=no
-fi
-rm -f core conftest.err conftest.$ac_objext \
-    conftest$ac_exeext conftest.$ac_ext
-LIBS=$ac_check_lib_save_LIBS
-fi
-{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $ac_cv_lib_png_png_set_expand_gray_1_2_4_to_8" >&5
-$as_echo "$ac_cv_lib_png_png_set_expand_gray_1_2_4_to_8" >&6; }
-if test "x$ac_cv_lib_png_png_set_expand_gray_1_2_4_to_8" = xyes; then :
-  cat >>confdefs.h <<_ACEOF
-#define HAVE_LIBPNG 1
-_ACEOF
-
-  LIBS="-lpng $LIBS"
-
-else
-  oldpng=1
-fi
-
-	if test $oldpng == 1
-	then
-		dodginess_options="$dodginess_options oldpng"
-		$as_echo "#define CVD_INTERNAL_HAVE_OLD_PNG 1" >>confdefs.h
-
-	fi
 
 
 		if test x$a == x
@@ -8980,6 +8824,9 @@ OFLAGS=$OFLAGS
 echo $CXXFLAGS
 echo $LIBS
 
+
+ac_config_headers="$ac_config_headers cvd/config.h"
+
 ac_config_files="$ac_config_files Makefile"
 
 cat >confcache <<\_ACEOF
@@ -9674,6 +9521,7 @@ cat >>$CONFIG_STATUS <<\_ACEOF || ac_write_fail=1
 for ac_config_target in $ac_config_targets
 do
   case $ac_config_target in
+    "cvd/config.h") CONFIG_HEADERS="$CONFIG_HEADERS cvd/config.h" ;;
     "Makefile") CONFIG_FILES="$CONFIG_FILES Makefile" ;;
 
   *) as_fn_error $? "invalid argument: \`$ac_config_target'" "$LINENO" 5;;
diff --git a/configure.ac b/configure.ac
index 739f1387..30166749 100644
--- a/configure.ac
+++ b/configure.ac
@@ -23,7 +23,6 @@ AC_DEFINE_UNQUOTED(CVD_MINOR_VERSION,$cvd_minor)
 AC_SUBST(minor, $cvd_minor)
 
 
-
 ################################################################################
 #
 #Lists of  optional components
@@ -571,40 +570,10 @@ CHECK_FOR_OPTION(videodisplay,[
 	
 ])
 
-CHECK_FOR_OPTION(shared_ptr, [
-	AC_MSG_CHECKING([for shared_ptr])
-	AC_COMPILE_IFELSE([AC_LANG_SOURCE([#include <memory>
-	int main(){std::shared_ptr<int> i; return  0;}])], [AC_MSG_RESULT(yes)],[AC_MSG_RESULT(no); a=1]) 
-	
-	if test x$a == x1
-	then
-		a=0
-		AC_MSG_CHECKING([for tr1::shared_ptr])
-		AC_COMPILE_IFELSE([AC_LANG_SOURCE([#include <tr1/memory>
-		int main(){std::tr1::shared_ptr<int> i; return  0;}])], [AC_MSG_RESULT(yes)],[AC_MSG_RESULT(no); a=1]) 
-		AC_DEFINE(CVD_INTERNAL_NEED_TR1)
-		APPEND(dodginess_options, tr1_shared_ptr)
-	fi
-])
-
-
 CHECK_FOR_OPTION(toon, [
 	AC_MSG_CHECKING([for TooN])
 	AC_COMPILE_IFELSE([AC_LANG_SOURCE([#include <TooN/TooN.h>
 	int main(){TooN::Vector<2, double> v=TooN::Zeros;return 0;}])], [AC_MSG_RESULT(yes)],[AC_MSG_RESULT(no); a=1]) 
-
-	if test x$a = x1 
-	then
-		AC_MSG_CHECKING([for old TooN])
-		AC_COMPILE_IFELSE([AC_LANG_SOURCE([#include <TooN/TooN.h>
-		int main(){TooN::Vector<2> v;return 0;}])], [AC_MSG_RESULT(yes)],[AC_MSG_RESULT(no); a=2]) 
-
-		if test x$a = x1
-		then
-			AC_MSG_WARN([Your version of TooN is too old. You need version 2.0-beta3 or later.])
-		fi
-		a=1
-	fi
 ])
 
 CHECK_FOR_OPTION(lapack, [
@@ -675,13 +644,6 @@ CHECK_FOR_OPTION(libuvc, [
 CHECK_FOR_OPTION(png, [
 	AC_CHECK_HEADERS(png.h, [], [a=1])
 	AC_CHECK_LIB(png, png_init_io, [], [a=1])
-	oldpng=0
-	AC_CHECK_LIB(png, png_set_expand_gray_1_2_4_to_8, [], [oldpng=1])
-	if test $oldpng == 1
-	then
-		APPEND(dodginess_options, oldpng)
-		AC_DEFINE(CVD_INTERNAL_HAVE_OLD_PNG, 1)
-	fi
 ])
 
 CHECK_FOR_OPTION(jpeg, [
@@ -1065,4 +1027,6 @@ AC_SUBST(OFLAGS, $OFLAGS)
 echo $CXXFLAGS
 echo $LIBS
 
+
+AC_CONFIG_HEADERS(cvd/config.h)
 AC_OUTPUT(Makefile)
diff --git a/cvd/Linux/v4lbuffer.h b/cvd/Linux/v4lbuffer.h
index dbf26dab..80c848dc 100644
--- a/cvd/Linux/v4lbuffer.h
+++ b/cvd/Linux/v4lbuffer.h
@@ -2,8 +2,6 @@
 #ifndef CVD_V4LBUFFER_H
 #define CVD_V4LBUFFER_H
 
-#include <cvd/config.h>
-
 #include <vector>
 
 #include <linux/videodev2.h>
diff --git a/cvd/config.h.in b/cvd/config.h.in
new file mode 100644
index 00000000..c5275f42
--- /dev/null
+++ b/cvd/config.h.in
@@ -0,0 +1,8 @@
+#ifndef CVD_INCLUDE_CONFIG_H_3216ac8
+#define CVD_INCLUDE_CONFIG_H_3216ac8
+
+	#undef CVD_HAVE_TOON
+	#undef CVD_HAVE_JPEG
+	#undef CVD_HAVE_PNG
+	#undef CVD_HAVE_TIFF
+#endif
diff --git a/cvd/cpu_hacks.h b/cvd/cpu_hacks.h
deleted file mode 100644
index cefbee6d..00000000
--- a/cvd/cpu_hacks.h
+++ /dev/null
@@ -1,92 +0,0 @@
-#ifndef CVD_CPU_HACKS_H
-#define CVD_CPU_HACKS_H
-
-
-#include <cvd/config.h>
-
-#if CVD_HAVE_FENV_H
-	#include <fenv.h>
-#endif
-
-#if CVD_HAVE_MMXEXT
-    #include <xmmintrin.h>
-#endif
-
-namespace CVD
-{
-
-
-	/// Enable floating point exceptions. This function may
-	/// do nothing, depending on the architecture
-	inline void enableFPE();
-
-	#ifndef DOXYGEN_IGNORE_INTERNAL
-		#ifdef CVD_HAVE_FENV_H
-			inline void enableFPE() 
-			{ 
-				feclearexcept(FE_ALL_EXCEPT);
-				feenableexcept(FE_DIVBYZERO|FE_INVALID); 
-			}
-		#else
-			/// Enable floating point exceptions. This function may
-			/// do nothing, depending on the architecture
-			inline void enableFPE() 
-			{ 
-			}
-		#endif
-	#endif
-
-	/// Prefetch memory. This function might do nothing, depending on the
-	/// architecture, or it might prefetch memory. Either way it will have
-	/// no effect on the computation except to (possibly) speed it up.
-	/// @param ptr The address of the memory to prefetch.
-	/// @param I   The type of prefetch. This depends on the architecture.
-	///            	- x86, MMXEXT
-	///					- 0: prefetcht0
-	///					- 1: prefetcht1
-	///					- 2: prefetcht2
-	///					- *: prefetchnta  (default)
-	///				- Everything else
-	///					- *: nothing
-	template<int I> inline void prefetch(const void* ptr);
-	
-	inline void prefetch(const void* ptr);
-
-
-	#ifndef DOXYGEN_IGNORE_INTERNAL
-		#ifdef  CVD_HAVE_MMXEXT	
-			template<int I> inline void prefetch(const void* ptr)
-			{
-                _mm_prefetch((char *)ptr, _MM_HINT_NTA);
-			}
-
-			template<> inline void prefetch<0>(const void* ptr)
-			{
-				_mm_prefetch((char *)ptr, _MM_HINT_T0);
-			}
-			
-			template<> inline void prefetch<1>(const void* ptr)
-			{
-				_mm_prefetch((char *)ptr, _MM_HINT_T1);
-			}
-
-			template<> inline void prefetch<2>(const void* ptr)
-			{
-                _mm_prefetch((char *)ptr, _MM_HINT_T2);
-			}
-		
-			inline void prefetch(const void* ptr)
-			{
-				prefetch<-1>(ptr);
-			}
-
-		#else
-			template<int i> inline void prefetch(const void*){}
-			inline void prefetch(const void*){}
-
-		#endif
-	#endif
-}
-#endif
-
-
diff --git a/cvd/image_io.h b/cvd/image_io.h
index 9d6f249e..1930e47b 100644
--- a/cvd/image_io.h
+++ b/cvd/image_io.h
@@ -80,16 +80,22 @@ namespace CVD
 			PNM = 0 , 
 			/// JPEG image format. This is a compressed (lossy) image format, but defaults to 95% quality, which has very few compression artefacts. This image type is only present if libjpeg is available.
 			/// RGB and Greyscale JPEGs are supported
+			#ifdef CVD_HAVE_JPEG
 			JPEG = 1,
+			#endif
 			/// Windows BMP (or DIB) format. Uncompressed 8 bit grey scale and 24 bit RGB are supported.
 			BMP = 2,
 			/// PNG image format. 1, 8 and 16 bit, Greyscale, RGB and RGBA images are supported.
 			/// This image type is only present if libpng is available.
+			#ifdef CVD_HAVE_PNG
 			PNG = 3,
+			#endif
 			/// TIFF image format. 1, 8, 16, 32 (float) and 64 (double) suported. Greyscale, RGB and RGBA supported.
 			/// This image type is only present if libtiff is available. G4 FAX encoding is used for bools, otherwise
 			/// "Deflate" compression is used.
+			#ifdef CVD_HAVE_TIFF
 			TIFF = 4,
+			#endif
 			/// Postscript  format. This outputs a bare PostScript image with the coordinate system set up 
 			/// to that (x,y) corresponds to pixel (x,y), with (0,0) being at the top left of the pixel (0,0).
 			/// The Y axis is therefore inverted compared to normal postscript drawing, but is image aligned.
diff --git a/m4/ax_prefix_config_h.m4 b/m4/ax_prefix_config_h.m4
new file mode 100644
index 00000000..22acbac6
--- /dev/null
+++ b/m4/ax_prefix_config_h.m4
@@ -0,0 +1,203 @@
+# ===========================================================================
+#    https://www.gnu.org/software/autoconf-archive/ax_prefix_config_h.html
+# ===========================================================================
+#
+# SYNOPSIS
+#
+#   AX_PREFIX_CONFIG_H [(OUTPUT-HEADER [,PREFIX [,ORIG-HEADER]])]
+#
+# DESCRIPTION
+#
+#   Generate an installable config.h.
+#
+#   A package should not normally install its config.h as a system header,
+#   but if it must, this macro can be used to avoid namespace pollution by
+#   making a copy of config.h with a prefix added to all the macro names.
+#
+#   Each "#define SOMEDEF" line of the configuration header has the given
+#   prefix added, in the same case as the first character of the macro name.
+#
+#   Defaults:
+#
+#     OUTPUT-HEADER = $PACKAGE-config.h
+#     PREFIX = $PACKAGE
+#     ORIG-HEADER, from AM_CONFIG_HEADER(config.h)
+#
+#   Your configure.ac script should contain both macros in this order.
+#
+#   Example:
+#
+#     AC_INIT(config.h.in)        # config.h.in as created by "autoheader"
+#     AM_INIT_AUTOMAKE(testpkg, 0.1.1)    # makes #undef VERSION and PACKAGE
+#     AM_CONFIG_HEADER(config.h)          # prep config.h from config.h.in
+#     AX_PREFIX_CONFIG_H(mylib/_config.h) # prep mylib/_config.h from it..
+#     AC_MEMORY_H                         # makes "#undef NEED_MEMORY_H"
+#     AC_C_CONST_H                        # makes "#undef const"
+#     AC_OUTPUT(Makefile)                 # creates the "config.h" now
+#                                         # and also mylib/_config.h
+#
+#   If the argument to AX_PREFIX_CONFIG_H would have been omitted then the
+#   default output file would have been called simply "testpkg-config.h",
+#   but even under the name "mylib/_config.h" it contains prefix-defines
+#   like
+#
+#     #ifndef TESTPKG_VERSION
+#     #define TESTPKG_VERSION "0.1.1"
+#     #endif
+#     #ifndef TESTPKG_NEED_MEMORY_H
+#     #define TESTPKG_NEED_MEMORY_H 1
+#     #endif
+#     #ifndef _testpkg_const
+#     #define _testpkg_const _const
+#     #endif
+#
+#   and this "mylib/_config.h" can be installed along with other header
+#   files, which is most convenient when creating a shared library (that has
+#   some headers) whose functionality depends on features detected at
+#   compile-time. No need to invent some "mylib-confdefs.h.in" manually.
+#
+#   Note that some AC_DEFINEs that end up in the config.h file are actually
+#   self-referential - e.g. AC_C_INLINE, AC_C_CONST, and the AC_TYPE_OFF_T
+#   say that they "will define inline|const|off_t if the system does not do
+#   it by itself". You might want to clean up about these - consider an
+#   extra mylib/conf.h that reads something like:
+#
+#     #include <mylib/_config.h>
+#     #ifndef _testpkg_const
+#     #define _testpkg_const const
+#     #endif
+#
+#   and then start using _testpkg_const in the header files. That is also a
+#   good thing to differentiate whether some library-user has starting to
+#   take up with a different compiler, so perhaps it could read something
+#   like this:
+#
+#     #ifdef _MSC_VER
+#     #include <mylib/_msvc.h>
+#     #else
+#     #include <mylib/_config.h>
+#     #endif
+#     #ifndef _testpkg_const
+#     #define _testpkg_const const
+#     #endif
+#
+# LICENSE
+#
+#   Copyright (c) 2014 Reuben Thomas <rrt@sc3d.org>
+#   Copyright (c) 2008 Guido U. Draheim <guidod@gmx.de>
+#   Copyright (c) 2008 Marten Svantesson
+#   Copyright (c) 2008 Gerald Point <Gerald.Point@labri.fr>
+#
+#   This program is free software; you can redistribute it and/or modify it
+#   under the terms of the GNU General Public License as published by the
+#   Free Software Foundation; either version 3 of the License, or (at your
+#   option) any later version.
+#
+#   This program is distributed in the hope that it will be useful, but
+#   WITHOUT ANY WARRANTY; without even the implied warranty of
+#   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General
+#   Public License for more details.
+#
+#   You should have received a copy of the GNU General Public License along
+#   with this program. If not, see <https://www.gnu.org/licenses/>.
+#
+#   As a special exception, the respective Autoconf Macro's copyright owner
+#   gives unlimited permission to copy, distribute and modify the configure
+#   scripts that are the output of Autoconf when processing the Macro. You
+#   need not follow the terms of the GNU General Public License when using
+#   or distributing such scripts, even though portions of the text of the
+#   Macro appear in them. The GNU General Public License (GPL) does govern
+#   all other use of the material that constitutes the Autoconf Macro.
+#
+#   This special exception to the GPL applies to versions of the Autoconf
+#   Macro released by the Autoconf Archive. When you make and distribute a
+#   modified version of the Autoconf Macro, you may extend this special
+#   exception to the GPL to apply to your modified version as well.
+
+#serial 16
+
+AC_DEFUN([AX_PREFIX_CONFIG_H],[dnl
+AC_PREREQ([2.62])
+AC_BEFORE([AC_CONFIG_HEADERS],[$0])dnl
+AC_CONFIG_COMMANDS(m4_default([$1], [$PACKAGE-config.h]),[dnl
+AS_VAR_PUSHDEF([_OUT],[ac_prefix_conf_OUT])dnl
+AS_VAR_PUSHDEF([_DEF],[ac_prefix_conf_DEF])dnl
+AS_VAR_PUSHDEF([_PKG],[ac_prefix_conf_PKG])dnl
+AS_VAR_PUSHDEF([_LOW],[ac_prefix_conf_LOW])dnl
+AS_VAR_PUSHDEF([_UPP],[ac_prefix_conf_UPP])dnl
+AS_VAR_PUSHDEF([_INP],[ac_prefix_conf_INP])dnl
+m4_pushdef([_script],[conftest.prefix])dnl
+m4_pushdef([_symbol],[m4_cr_Letters[]m4_cr_digits[]_])dnl
+_OUT=`echo m4_default([$1], [$PACKAGE-config.h])`
+_DEF=`echo _$_OUT | sed -e "y:m4_cr_letters:m4_cr_LETTERS[]:" -e "s/@<:@^m4_cr_Letters@:>@/_/g"`
+_PKG=`echo m4_default([$2], [$PACKAGE])`
+_LOW=`echo _$_PKG | sed -e "y:m4_cr_LETTERS-:m4_cr_letters[]_:"`
+_UPP=`echo $_PKG | sed -e "y:m4_cr_letters-:m4_cr_LETTERS[]_:"  -e "/^@<:@m4_cr_digits@:>@/s/^/_/"`
+_INP=`echo "$3" | sed -e 's/ *//'`
+if test ".$_INP" = "."; then
+   for ac_file in : $CONFIG_HEADERS; do test "_$ac_file" = _: && continue
+     case "$ac_file" in
+        *.h) _INP=$ac_file ;;
+        *)
+     esac
+     test ".$_INP" != "." && break
+   done
+fi
+if test ".$_INP" = "."; then
+   case "$_OUT" in
+      */*) _INP=`basename "$_OUT"`
+      ;;
+      *-*) _INP=`echo "$_OUT" | sed -e "s/@<:@_symbol@:>@*-//"`
+      ;;
+      *) _INP=config.h
+      ;;
+   esac
+fi
+if test -z "$_PKG" ; then
+   AC_MSG_ERROR([no prefix for _PREFIX_PKG_CONFIG_H])
+else
+  if test ! -f "$_INP" ; then if test -f "$srcdir/$_INP" ; then
+     _INP="$srcdir/$_INP"
+  fi fi
+  AC_MSG_NOTICE(creating $_OUT - prefix $_UPP for $_INP defines)
+  if test -f $_INP ; then
+    AS_ECHO(["s/^@%:@undef  *\\(@<:@m4_cr_LETTERS[]_@:>@\\)/@%:@undef $_UPP""_\\1/"]) > _script
+    AS_ECHO(["s/^@%:@undef  *\\(@<:@m4_cr_letters@:>@\\)/@%:@undef $_LOW""_\\1/"]) >> _script
+    AS_ECHO(["s/^@%:@def[]ine  *\\(@<:@m4_cr_LETTERS[]_@:>@@<:@_symbol@:>@*\\)\\(.*\\)/@%:@ifndef $_UPP""_\\1\\"]) >> _script
+    AS_ECHO(["@%:@def[]ine $_UPP""_\\1\\2\\"]) >> _script
+    AS_ECHO(["@%:@endif/"]) >> _script
+    AS_ECHO(["s/^@%:@def[]ine  *\\(@<:@m4_cr_letters@:>@@<:@_symbol@:>@*\\)\\(.*\\)/@%:@ifndef $_LOW""_\\1\\"]) >> _script
+    AS_ECHO(["@%:@define $_LOW""_\\1\\2\\"]) >> _script
+    AS_ECHO(["@%:@endif/"]) >> _script
+    # now executing _script on _DEF input to create _OUT output file
+    echo "@%:@ifndef $_DEF"      >$tmp/pconfig.h
+    echo "@%:@def[]ine $_DEF 1" >>$tmp/pconfig.h
+    echo ' ' >>$tmp/pconfig.h
+    echo /'*' $_OUT. Generated automatically at end of configure. '*'/ >>$tmp/pconfig.h
+
+    sed -f _script $_INP >>$tmp/pconfig.h
+    echo ' ' >>$tmp/pconfig.h
+    echo '/* once:' $_DEF '*/' >>$tmp/pconfig.h
+    echo "@%:@endif" >>$tmp/pconfig.h
+    if cmp -s $_OUT $tmp/pconfig.h 2>/dev/null; then
+      AC_MSG_NOTICE([$_OUT is unchanged])
+    else
+      ac_dir=`AS_DIRNAME(["$_OUT"])`
+      AS_MKDIR_P(["$ac_dir"])
+      rm -f "$_OUT"
+      mv $tmp/pconfig.h "$_OUT"
+    fi
+  else
+    AC_MSG_ERROR([input file $_INP does not exist - skip generating $_OUT])
+  fi
+  rm -f conftest.*
+fi
+m4_popdef([_symbol])dnl
+m4_popdef([_script])dnl
+AS_VAR_POPDEF([_INP])dnl
+AS_VAR_POPDEF([_UPP])dnl
+AS_VAR_POPDEF([_LOW])dnl
+AS_VAR_POPDEF([_PKG])dnl
+AS_VAR_POPDEF([_DEF])dnl
+AS_VAR_POPDEF([_OUT])dnl
+],[PACKAGE="$PACKAGE"])])