diff --git a/.gitignore b/.gitignore
index d719cba..e1a4fcd 100644
--- a/.gitignore
+++ b/.gitignore
@@ -11,3 +11,4 @@ autom4te.cache/
 src/config.h.in~
 src/*.o
 src/*.exe
+src/version.h
diff --git a/AUTHORS b/AUTHORS
index 7bb4470..9e8ef2a 100644
--- a/AUTHORS
+++ b/AUTHORS
@@ -1 +1 @@
-Thanassis Tsiodras <ttsiod@softlab.ntua.gr>
+Thanassis Tsiodras <ttsiodras@gmail.com>
diff --git a/Makefile.in b/Makefile.in
index 5431262..3406784 100644
--- a/Makefile.in
+++ b/Makefile.in
@@ -1,7 +1,7 @@
-# Makefile.in generated by automake 1.16.2 from Makefile.am.
+# Makefile.in generated by automake 1.15 from Makefile.am.
 # @configure_input@
 
-# Copyright (C) 1994-2020 Free Software Foundation, Inc.
+# Copyright (C) 1994-2014 Free Software Foundation, Inc.
 
 # This Makefile.in is free software; the Free Software Foundation
 # gives unlimited permission to copy and/or distribute it,
@@ -93,6 +93,7 @@ ACLOCAL_M4 = $(top_srcdir)/aclocal.m4
 am__aclocal_m4_deps = $(top_srcdir)/acinclude.m4 \
 	$(top_srcdir)/ac-macros/ax_openmp.m4 \
 	$(top_srcdir)/ac-macros/ax_cflags_gcc_option.m4 \
+	$(top_srcdir)/ac-macros/revision_utils.m4 \
 	$(top_srcdir)/configure.ac
 am__configure_deps = $(am__aclocal_m4_deps) $(CONFIGURE_DEPENDENCIES) \
 	$(ACLOCAL_M4)
@@ -138,7 +139,7 @@ am__recursive_targets = \
   $(RECURSIVE_CLEAN_TARGETS) \
   $(am__extra_recursive_targets)
 AM_RECURSIVE_TARGETS = $(am__recursive_targets:-recursive=) TAGS CTAGS \
-	cscope distdir distdir-am dist dist-all distcheck
+	cscope distdir dist dist-all distcheck
 am__tagged_files = $(HEADERS) $(SOURCES) $(TAGS_FILES) $(LISP)
 # Read a list of newline-separated strings from the standard input,
 # and print each of them once, without duplicates.  Input order is
@@ -237,6 +238,8 @@ INSTALL_DATA = @INSTALL_DATA@
 INSTALL_PROGRAM = @INSTALL_PROGRAM@
 INSTALL_SCRIPT = @INSTALL_SCRIPT@
 INSTALL_STRIP_PROGRAM = @INSTALL_STRIP_PROGRAM@
+LAST_CONFIG_DATE = @LAST_CONFIG_DATE@
+LAST_CONFIG_YEAR = @LAST_CONFIG_YEAR@
 LDFLAGS = @LDFLAGS@
 LIBOBJS = @LIBOBJS@
 LIBS = @LIBS@
@@ -253,6 +256,7 @@ PACKAGE_TARNAME = @PACKAGE_TARNAME@
 PACKAGE_URL = @PACKAGE_URL@
 PACKAGE_VERSION = @PACKAGE_VERSION@
 PATH_SEPARATOR = @PATH_SEPARATOR@
+SCM_REVISION = @SCM_REVISION@
 SDL_CFLAGS = @SDL_CFLAGS@
 SDL_CONFIG = @SDL_CONFIG@
 SDL_LIBS = @SDL_LIBS@
@@ -302,6 +306,7 @@ pdfdir = @pdfdir@
 prefix = @prefix@
 program_transform_name = @program_transform_name@
 psdir = @psdir@
+runstatedir = @runstatedir@
 sbindir = @sbindir@
 sharedstatedir = @sharedstatedir@
 srcdir = @srcdir@
@@ -341,8 +346,8 @@ Makefile: $(srcdir)/Makefile.in $(top_builddir)/config.status
 	    echo ' $(SHELL) ./config.status'; \
 	    $(SHELL) ./config.status;; \
 	  *) \
-	    echo ' cd $(top_builddir) && $(SHELL) ./config.status $@ $(am__maybe_remake_depfiles)'; \
-	    cd $(top_builddir) && $(SHELL) ./config.status $@ $(am__maybe_remake_depfiles);; \
+	    echo ' cd $(top_builddir) && $(SHELL) ./config.status $@ $(am__depfiles_maybe)'; \
+	    cd $(top_builddir) && $(SHELL) ./config.status $@ $(am__depfiles_maybe);; \
 	esac;
 
 $(top_builddir)/config.status: $(top_srcdir)/configure $(CONFIG_STATUS_DEPENDENCIES)
@@ -460,10 +465,7 @@ distclean-tags:
 	-rm -f TAGS ID GTAGS GRTAGS GSYMS GPATH tags
 	-rm -f cscope.out cscope.in.out cscope.po.out cscope.files
 
-distdir: $(BUILT_SOURCES)
-	$(MAKE) $(AM_MAKEFLAGS) distdir-am
-
-distdir-am: $(DISTFILES)
+distdir: $(DISTFILES)
 	$(am__remove_distdir)
 	test -d "$(distdir)" || mkdir "$(distdir)"
 	@srcdirstrip=`echo "$(srcdir)" | sed 's/[].[^$$\\*]/\\\\&/g'`; \
@@ -528,7 +530,7 @@ distdir-am: $(DISTFILES)
 	  ! -type d ! -perm -444 -exec $(install_sh) -c -m a+r {} {} \; \
 	|| chmod -R a+r "$(distdir)"
 dist-gzip: distdir
-	tardir=$(distdir) && $(am__tar) | eval GZIP= gzip $(GZIP_ENV) -c >$(distdir).tar.gz
+	tardir=$(distdir) && $(am__tar) | GZIP=$(GZIP_ENV) gzip -c >$(distdir).tar.gz
 	$(am__post_remove_distdir)
 
 dist-bzip2: distdir
@@ -543,10 +545,6 @@ dist-xz: distdir
 	tardir=$(distdir) && $(am__tar) | XZ_OPT=$${XZ_OPT--e} xz -c >$(distdir).tar.xz
 	$(am__post_remove_distdir)
 
-dist-zstd: distdir
-	tardir=$(distdir) && $(am__tar) | zstd -c $${ZSTD_CLEVEL-$${ZSTD_OPT--19}} >$(distdir).tar.zst
-	$(am__post_remove_distdir)
-
 dist-tarZ: distdir
 	@echo WARNING: "Support for distribution archives compressed with" \
 		       "legacy program 'compress' is deprecated." >&2
@@ -558,7 +556,7 @@ dist-shar: distdir
 	@echo WARNING: "Support for shar distribution archives is" \
 	               "deprecated." >&2
 	@echo WARNING: "It will be removed altogether in Automake 2.0" >&2
-	shar $(distdir) | eval GZIP= gzip $(GZIP_ENV) -c >$(distdir).shar.gz
+	shar $(distdir) | GZIP=$(GZIP_ENV) gzip -c >$(distdir).shar.gz
 	$(am__post_remove_distdir)
 
 dist-zip: distdir
@@ -576,7 +574,7 @@ dist dist-all:
 distcheck: dist
 	case '$(DIST_ARCHIVES)' in \
 	*.tar.gz*) \
-	  eval GZIP= gzip $(GZIP_ENV) -dc $(distdir).tar.gz | $(am__untar) ;;\
+	  GZIP=$(GZIP_ENV) gzip -dc $(distdir).tar.gz | $(am__untar) ;;\
 	*.tar.bz2*) \
 	  bzip2 -dc $(distdir).tar.bz2 | $(am__untar) ;;\
 	*.tar.lz*) \
@@ -586,11 +584,9 @@ distcheck: dist
 	*.tar.Z*) \
 	  uncompress -c $(distdir).tar.Z | $(am__untar) ;;\
 	*.shar.gz*) \
-	  eval GZIP= gzip $(GZIP_ENV) -dc $(distdir).shar.gz | unshar ;;\
+	  GZIP=$(GZIP_ENV) gzip -dc $(distdir).shar.gz | unshar ;;\
 	*.zip*) \
 	  unzip $(distdir).zip ;;\
-	*.tar.zst*) \
-	  zstd -dc $(distdir).tar.zst | $(am__untar) ;;\
 	esac
 	chmod -R a-w $(distdir)
 	chmod u+w $(distdir)
@@ -768,7 +764,7 @@ uninstall-am:
 	am--refresh check check-am clean clean-cscope clean-generic \
 	cscope cscopelist-am ctags ctags-am dist dist-all dist-bzip2 \
 	dist-gzip dist-lzip dist-shar dist-tarZ dist-xz dist-zip \
-	dist-zstd distcheck distclean distclean-generic distclean-tags \
+	distcheck distclean distclean-generic distclean-tags \
 	distcleancheck distdir distuninstallcheck dvi dvi-am html \
 	html-am info info-am install install-am install-data \
 	install-data-am install-dvi install-dvi-am install-exec \
diff --git a/README.md b/README.md
index 21239ea..3aa60a9 100644
--- a/README.md
+++ b/README.md
@@ -9,7 +9,7 @@ COMPILE/INSTALL/RUN
 Windows
 -------
 Windows users can download and run a pre-compiled Windows binary
-[here](https://github.com/ttsiodras/MandelbrotSSE/releases/download/2.0/mandelSSE-win32-2.0.zip).
+[here](https://github.com/ttsiodras/MandelbrotSSE/releases/download/2.1/mandelSSE-win32-2.1.zip).
 
 After decompressing, you can simply execute either one of the two .bat
 files. The 'autopilot' one zooms in a specific location, while the other
diff --git a/ac-macros/revision_utils.m4 b/ac-macros/revision_utils.m4
new file mode 100644
index 0000000..c670989
--- /dev/null
+++ b/ac-macros/revision_utils.m4
@@ -0,0 +1,59 @@
+# Automake macro to set the revision utils
+
+# Usage: AM_REVISION_UTILS([directory_name]).
+# Directory name must be a litteral string and not the result of a
+# command.
+
+AC_DEFUN([AM_REVISION_UTILS],
+[
+# Take the current SVN revision
+
+AC_MSG_CHECKING(whether this is a SCM working copy)
+
+temp_scm_output=`(cd $srcdir; git rev-parse --short HEAD)`
+
+if test x"${temp_scm_output}" = x""; then
+   # This means we are NOT working on a repository copy, the value of
+   # SCM_REVISION will not be taken into account.
+
+   SCM_REVISION=""
+   AC_MSG_RESULT(no.)
+else
+   SCM_REVISION="r${temp_scm_output}"
+   AC_MSG_RESULT(yes: ${SCM_REVISION}.)
+fi
+
+AC_SUBST(SCM_REVISION)
+
+# Take the configure full date
+
+AC_MSG_CHECKING(the configuration full date)
+
+temp_config_date=`LANG=C date +"%A %d %B %Y, %H:%M:%S"`
+
+if test x"${temp_config_date}" = x""; then
+   LAST_CONFIG_DATE=""
+   AC_MSG_RESULT(empty date.)
+else
+   LAST_CONFIG_DATE="${temp_config_date}"
+   AC_MSG_RESULT(${LAST_CONFIG_DATE}.)
+fi
+
+AC_SUBST(LAST_CONFIG_DATE)
+
+# Take the configure year
+
+AC_MSG_CHECKING(the configuration year)
+
+temp_config_year=`LANG=C date +"%Y"`
+
+if test x"${temp_config_year}" = x""; then
+   LAST_CONFIG_YEAR="2007"
+   AC_MSG_RESULT(no year found, fall into default: ${LAST_CONFIG_YEAR}.)
+else
+   LAST_CONFIG_YEAR="${temp_config_year}"
+   AC_MSG_RESULT(${LAST_CONFIG_YEAR})
+fi
+
+AC_SUBST(LAST_CONFIG_YEAR)
+])
diff --git a/acinclude.m4 b/acinclude.m4
index e00b45d..af958e4 100644
--- a/acinclude.m4
+++ b/acinclude.m4
@@ -1,2 +1,3 @@
 m4_include([ac-macros/ax_openmp.m4])
 m4_include([ac-macros/ax_cflags_gcc_option.m4])
+m4_include([ac-macros/revision_utils.m4])
diff --git a/aclocal.m4 b/aclocal.m4
index 9fdec9d..5d40195 100644
--- a/aclocal.m4
+++ b/aclocal.m4
@@ -1,6 +1,6 @@
-# generated automatically by aclocal 1.16.2 -*- Autoconf -*-
+# generated automatically by aclocal 1.15 -*- Autoconf -*-
 
-# Copyright (C) 1996-2020 Free Software Foundation, Inc.
+# Copyright (C) 1996-2014 Free Software Foundation, Inc.
 
 # This file is free software; the Free Software Foundation
 # gives unlimited permission to copy and/or distribute it,
@@ -206,7 +206,7 @@ int main(int argc, char *argv[])
   rm -f conf.sdltest
 ])
 
-# Copyright (C) 2002-2020 Free Software Foundation, Inc.
+# Copyright (C) 2002-2014 Free Software Foundation, Inc.
 #
 # This file is free software; the Free Software Foundation
 # gives unlimited permission to copy and/or distribute it,
@@ -218,10 +218,10 @@ int main(int argc, char *argv[])
 # generated from the m4 files accompanying Automake X.Y.
 # (This private macro should not be called outside this file.)
 AC_DEFUN([AM_AUTOMAKE_VERSION],
-[am__api_version='1.16'
+[am__api_version='1.15'
 dnl Some users find AM_AUTOMAKE_VERSION and mistake it for a way to
 dnl require some minimum version.  Point them to the right macro.
-m4_if([$1], [1.16.2], [],
+m4_if([$1], [1.15], [],
       [AC_FATAL([Do not call $0, use AM_INIT_AUTOMAKE([$1]).])])dnl
 ])
 
@@ -237,14 +237,14 @@ m4_define([_AM_AUTOCONF_VERSION], [])
 # Call AM_AUTOMAKE_VERSION and AM_AUTOMAKE_VERSION so they can be traced.
 # This function is AC_REQUIREd by AM_INIT_AUTOMAKE.
 AC_DEFUN([AM_SET_CURRENT_AUTOMAKE_VERSION],
-[AM_AUTOMAKE_VERSION([1.16.2])dnl
+[AM_AUTOMAKE_VERSION([1.15])dnl
 m4_ifndef([AC_AUTOCONF_VERSION],
   [m4_copy([m4_PACKAGE_VERSION], [AC_AUTOCONF_VERSION])])dnl
 _AM_AUTOCONF_VERSION(m4_defn([AC_AUTOCONF_VERSION]))])
 
 # AM_AUX_DIR_EXPAND                                         -*- Autoconf -*-
 
-# Copyright (C) 2001-2020 Free Software Foundation, Inc.
+# Copyright (C) 2001-2014 Free Software Foundation, Inc.
 #
 # This file is free software; the Free Software Foundation
 # gives unlimited permission to copy and/or distribute it,
@@ -296,7 +296,7 @@ am_aux_dir=`cd "$ac_aux_dir" && pwd`
 
 # AM_CONDITIONAL                                            -*- Autoconf -*-
 
-# Copyright (C) 1997-2020 Free Software Foundation, Inc.
+# Copyright (C) 1997-2014 Free Software Foundation, Inc.
 #
 # This file is free software; the Free Software Foundation
 # gives unlimited permission to copy and/or distribute it,
@@ -327,7 +327,7 @@ AC_CONFIG_COMMANDS_PRE(
 Usually this means the macro was only invoked conditionally.]])
 fi])])
 
-# Copyright (C) 1999-2020 Free Software Foundation, Inc.
+# Copyright (C) 1999-2014 Free Software Foundation, Inc.
 #
 # This file is free software; the Free Software Foundation
 # gives unlimited permission to copy and/or distribute it,
@@ -518,12 +518,13 @@ _AM_SUBST_NOTMAKE([am__nodep])dnl
 
 # Generate code to set up dependency tracking.              -*- Autoconf -*-
 
-# Copyright (C) 1999-2020 Free Software Foundation, Inc.
+# Copyright (C) 1999-2014 Free Software Foundation, Inc.
 #
 # This file is free software; the Free Software Foundation
 # gives unlimited permission to copy and/or distribute it,
 # with or without modifications, as long as this notice is preserved.
 
+
 # _AM_OUTPUT_DEPENDENCY_COMMANDS
 # ------------------------------
 AC_DEFUN([_AM_OUTPUT_DEPENDENCY_COMMANDS],
@@ -531,43 +532,49 @@ AC_DEFUN([_AM_OUTPUT_DEPENDENCY_COMMANDS],
   # Older Autoconf quotes --file arguments for eval, but not when files
   # are listed without --file.  Let's play safe and only enable the eval
   # if we detect the quoting.
-  # TODO: see whether this extra hack can be removed once we start
-  # requiring Autoconf 2.70 or later.
-  AS_CASE([$CONFIG_FILES],
-          [*\'*], [eval set x "$CONFIG_FILES"],
-          [*], [set x $CONFIG_FILES])
+  case $CONFIG_FILES in
+  *\'*) eval set x "$CONFIG_FILES" ;;
+  *)   set x $CONFIG_FILES ;;
+  esac
   shift
-  # Used to flag and report bootstrapping failures.
-  am_rc=0
-  for am_mf
+  for mf
   do
     # Strip MF so we end up with the name of the file.
-    am_mf=`AS_ECHO(["$am_mf"]) | sed -e 's/:.*$//'`
-    # Check whether this is an Automake generated Makefile which includes
-    # dependency-tracking related rules and includes.
-    # Grep'ing the whole file directly is not great: AIX grep has a line
+    mf=`echo "$mf" | sed -e 's/:.*$//'`
+    # Check whether this is an Automake generated Makefile or not.
+    # We used to match only the files named 'Makefile.in', but
+    # some people rename them; so instead we look at the file content.
+    # Grep'ing the first line is not enough: some people post-process
+    # each Makefile.in and add a new line on top of each file to say so.
+    # Grep'ing the whole file is not good either: AIX grep has a line
     # limit of 2048, but all sed's we know have understand at least 4000.
-    sed -n 's,^am--depfiles:.*,X,p' "$am_mf" | grep X >/dev/null 2>&1 \
-      || continue
-    am_dirpart=`AS_DIRNAME(["$am_mf"])`
-    am_filepart=`AS_BASENAME(["$am_mf"])`
-    AM_RUN_LOG([cd "$am_dirpart" \
-      && sed -e '/# am--include-marker/d' "$am_filepart" \
-        | $MAKE -f - am--depfiles]) || am_rc=$?
+    if sed -n 's,^#.*generated by automake.*,X,p' "$mf" | grep X >/dev/null 2>&1; then
+      dirpart=`AS_DIRNAME("$mf")`
+    else
+      continue
+    fi
+    # Extract the definition of DEPDIR, am__include, and am__quote
+    # from the Makefile without running 'make'.
+    DEPDIR=`sed -n 's/^DEPDIR = //p' < "$mf"`
+    test -z "$DEPDIR" && continue
+    am__include=`sed -n 's/^am__include = //p' < "$mf"`
+    test -z "$am__include" && continue
+    am__quote=`sed -n 's/^am__quote = //p' < "$mf"`
+    # Find all dependency output files, they are included files with
+    # $(DEPDIR) in their names.  We invoke sed twice because it is the
+    # simplest approach to changing $(DEPDIR) to its actual value in the
+    # expansion.
+    for file in `sed -n "
+      s/^$am__include $am__quote\(.*(DEPDIR).*\)$am__quote"'$/\1/p' <"$mf" | \
+	 sed -e 's/\$(DEPDIR)/'"$DEPDIR"'/g'`; do
+      # Make sure the directory exists.
+      test -f "$dirpart/$file" && continue
+      fdir=`AS_DIRNAME(["$file"])`
+      AS_MKDIR_P([$dirpart/$fdir])
+      # echo "creating $dirpart/$file"
+      echo '# dummy' > "$dirpart/$file"
+    done
   done
-  if test $am_rc -ne 0; then
-    AC_MSG_FAILURE([Something went wrong bootstrapping makefile fragments
-    for automatic dependency tracking.  If GNU make was not used, consider
-    re-running the configure script with MAKE="gmake" (or whatever is
-    necessary).  You can also try re-running configure with the
-    '--disable-dependency-tracking' option to at least be able to build
-    the package (albeit without support for automatic dependency tracking).])
-  fi
-  AS_UNSET([am_dirpart])
-  AS_UNSET([am_filepart])
-  AS_UNSET([am_mf])
-  AS_UNSET([am_rc])
-  rm -f conftest-deps.mk
 }
 ])# _AM_OUTPUT_DEPENDENCY_COMMANDS
 
@@ -576,17 +583,18 @@ AC_DEFUN([_AM_OUTPUT_DEPENDENCY_COMMANDS],
 # -----------------------------
 # This macro should only be invoked once -- use via AC_REQUIRE.
 #
-# This code is only required when automatic dependency tracking is enabled.
-# This creates each '.Po' and '.Plo' makefile fragment that we'll need in
-# order to bootstrap the dependency handling code.
+# This code is only required when automatic dependency tracking
+# is enabled.  FIXME.  This creates each '.P' file that we will
+# need in order to bootstrap the dependency handling code.
 AC_DEFUN([AM_OUTPUT_DEPENDENCY_COMMANDS],
 [AC_CONFIG_COMMANDS([depfiles],
      [test x"$AMDEP_TRUE" != x"" || _AM_OUTPUT_DEPENDENCY_COMMANDS],
-     [AMDEP_TRUE="$AMDEP_TRUE" MAKE="${MAKE-make}"])])
+     [AMDEP_TRUE="$AMDEP_TRUE" ac_aux_dir="$ac_aux_dir"])
+])
 
 # Do all the work for Automake.                             -*- Autoconf -*-
 
-# Copyright (C) 1996-2020 Free Software Foundation, Inc.
+# Copyright (C) 1996-2014 Free Software Foundation, Inc.
 #
 # This file is free software; the Free Software Foundation
 # gives unlimited permission to copy and/or distribute it,
@@ -673,8 +681,8 @@ AC_REQUIRE([AM_PROG_INSTALL_STRIP])dnl
 AC_REQUIRE([AC_PROG_MKDIR_P])dnl
 # For better backward compatibility.  To be removed once Automake 1.9.x
 # dies out for good.  For more background, see:
-# <https://lists.gnu.org/archive/html/automake/2012-07/msg00001.html>
-# <https://lists.gnu.org/archive/html/automake/2012-07/msg00014.html>
+# <http://lists.gnu.org/archive/html/automake/2012-07/msg00001.html>
+# <http://lists.gnu.org/archive/html/automake/2012-07/msg00014.html>
 AC_SUBST([mkdir_p], ['$(MKDIR_P)'])
 # We need awk for the "check" target (and possibly the TAP driver).  The
 # system "awk" is bad on some platforms.
@@ -741,7 +749,7 @@ END
 Aborting the configuration process, to ensure you take notice of the issue.
 
 You can download and install GNU coreutils to get an 'rm' implementation
-that behaves properly: <https://www.gnu.org/software/coreutils/>.
+that behaves properly: <http://www.gnu.org/software/coreutils/>.
 
 If you want to complete the configuration process using your problematic
 'rm' anyway, export the environment variable ACCEPT_INFERIOR_RM_PROGRAM
@@ -783,7 +791,7 @@ for _am_header in $config_headers :; do
 done
 echo "timestamp for $_am_arg" >`AS_DIRNAME(["$_am_arg"])`/stamp-h[]$_am_stamp_count])
 
-# Copyright (C) 2001-2020 Free Software Foundation, Inc.
+# Copyright (C) 2001-2014 Free Software Foundation, Inc.
 #
 # This file is free software; the Free Software Foundation
 # gives unlimited permission to copy and/or distribute it,
@@ -804,7 +812,7 @@ if test x"${install_sh+set}" != xset; then
 fi
 AC_SUBST([install_sh])])
 
-# Copyright (C) 2003-2020 Free Software Foundation, Inc.
+# Copyright (C) 2003-2014 Free Software Foundation, Inc.
 #
 # This file is free software; the Free Software Foundation
 # gives unlimited permission to copy and/or distribute it,
@@ -825,7 +833,7 @@ AC_SUBST([am__leading_dot])])
 
 # Check to see how 'make' treats includes.	            -*- Autoconf -*-
 
-# Copyright (C) 2001-2020 Free Software Foundation, Inc.
+# Copyright (C) 2001-2014 Free Software Foundation, Inc.
 #
 # This file is free software; the Free Software Foundation
 # gives unlimited permission to copy and/or distribute it,
@@ -833,42 +841,49 @@ AC_SUBST([am__leading_dot])])
 
 # AM_MAKE_INCLUDE()
 # -----------------
-# Check whether make has an 'include' directive that can support all
-# the idioms we need for our automatic dependency tracking code.
+# Check to see how make treats includes.
 AC_DEFUN([AM_MAKE_INCLUDE],
-[AC_MSG_CHECKING([whether ${MAKE-make} supports the include directive])
-cat > confinc.mk << 'END'
+[am_make=${MAKE-make}
+cat > confinc << 'END'
 am__doit:
-	@echo this is the am__doit target >confinc.out
+	@echo this is the am__doit target
 .PHONY: am__doit
 END
+# If we don't find an include directive, just comment out the code.
+AC_MSG_CHECKING([for style of include used by $am_make])
 am__include="#"
 am__quote=
-# BSD make does it like this.
-echo '.include "confinc.mk" # ignored' > confmf.BSD
-# Other make implementations (GNU, Solaris 10, AIX) do it like this.
-echo 'include confinc.mk # ignored' > confmf.GNU
-_am_result=no
-for s in GNU BSD; do
-  AM_RUN_LOG([${MAKE-make} -f confmf.$s && cat confinc.out])
-  AS_CASE([$?:`cat confinc.out 2>/dev/null`],
-      ['0:this is the am__doit target'],
-      [AS_CASE([$s],
-          [BSD], [am__include='.include' am__quote='"'],
-          [am__include='include' am__quote=''])])
-  if test "$am__include" != "#"; then
-    _am_result="yes ($s style)"
-    break
-  fi
-done
-rm -f confinc.* confmf.*
-AC_MSG_RESULT([${_am_result}])
-AC_SUBST([am__include])])
-AC_SUBST([am__quote])])
+_am_result=none
+# First try GNU make style include.
+echo "include confinc" > confmf
+# Ignore all kinds of additional output from 'make'.
+case `$am_make -s -f confmf 2> /dev/null` in #(
+*the\ am__doit\ target*)
+  am__include=include
+  am__quote=
+  _am_result=GNU
+  ;;
+esac
+# Now try BSD make style include.
+if test "$am__include" = "#"; then
+   echo '.include "confinc"' > confmf
+   case `$am_make -s -f confmf 2> /dev/null` in #(
+   *the\ am__doit\ target*)
+     am__include=.include
+     am__quote="\""
+     _am_result=BSD
+     ;;
+   esac
+fi
+AC_SUBST([am__include])
+AC_SUBST([am__quote])
+AC_MSG_RESULT([$_am_result])
+rm -f confinc confmf
+])
 
 # Fake the existence of programs that GNU maintainers use.  -*- Autoconf -*-
 
-# Copyright (C) 1997-2020 Free Software Foundation, Inc.
+# Copyright (C) 1997-2014 Free Software Foundation, Inc.
 #
 # This file is free software; the Free Software Foundation
 # gives unlimited permission to copy and/or distribute it,
@@ -907,7 +922,7 @@ fi
 
 # Helper functions for option handling.                     -*- Autoconf -*-
 
-# Copyright (C) 2001-2020 Free Software Foundation, Inc.
+# Copyright (C) 2001-2014 Free Software Foundation, Inc.
 #
 # This file is free software; the Free Software Foundation
 # gives unlimited permission to copy and/or distribute it,
@@ -936,7 +951,7 @@ AC_DEFUN([_AM_SET_OPTIONS],
 AC_DEFUN([_AM_IF_OPTION],
 [m4_ifset(_AM_MANGLE_OPTION([$1]), [$2], [$3])])
 
-# Copyright (C) 1999-2020 Free Software Foundation, Inc.
+# Copyright (C) 1999-2014 Free Software Foundation, Inc.
 #
 # This file is free software; the Free Software Foundation
 # gives unlimited permission to copy and/or distribute it,
@@ -983,7 +998,7 @@ AC_LANG_POP([C])])
 # For backward compatibility.
 AC_DEFUN_ONCE([AM_PROG_CC_C_O], [AC_REQUIRE([AC_PROG_CC])])
 
-# Copyright (C) 2001-2020 Free Software Foundation, Inc.
+# Copyright (C) 2001-2014 Free Software Foundation, Inc.
 #
 # This file is free software; the Free Software Foundation
 # gives unlimited permission to copy and/or distribute it,
@@ -1002,7 +1017,7 @@ AC_DEFUN([AM_RUN_LOG],
 
 # Check to make sure that the build environment is sane.    -*- Autoconf -*-
 
-# Copyright (C) 1996-2020 Free Software Foundation, Inc.
+# Copyright (C) 1996-2014 Free Software Foundation, Inc.
 #
 # This file is free software; the Free Software Foundation
 # gives unlimited permission to copy and/or distribute it,
@@ -1083,7 +1098,7 @@ AC_CONFIG_COMMANDS_PRE(
 rm -f conftest.file
 ])
 
-# Copyright (C) 2009-2020 Free Software Foundation, Inc.
+# Copyright (C) 2009-2014 Free Software Foundation, Inc.
 #
 # This file is free software; the Free Software Foundation
 # gives unlimited permission to copy and/or distribute it,
@@ -1143,7 +1158,7 @@ AC_SUBST([AM_BACKSLASH])dnl
 _AM_SUBST_NOTMAKE([AM_BACKSLASH])dnl
 ])
 
-# Copyright (C) 2001-2020 Free Software Foundation, Inc.
+# Copyright (C) 2001-2014 Free Software Foundation, Inc.
 #
 # This file is free software; the Free Software Foundation
 # gives unlimited permission to copy and/or distribute it,
@@ -1171,7 +1186,7 @@ fi
 INSTALL_STRIP_PROGRAM="\$(install_sh) -c -s"
 AC_SUBST([INSTALL_STRIP_PROGRAM])])
 
-# Copyright (C) 2006-2020 Free Software Foundation, Inc.
+# Copyright (C) 2006-2014 Free Software Foundation, Inc.
 #
 # This file is free software; the Free Software Foundation
 # gives unlimited permission to copy and/or distribute it,
@@ -1190,7 +1205,7 @@ AC_DEFUN([AM_SUBST_NOTMAKE], [_AM_SUBST_NOTMAKE($@)])
 
 # Check how to create a tarball.                            -*- Autoconf -*-
 
-# Copyright (C) 2004-2020 Free Software Foundation, Inc.
+# Copyright (C) 2004-2014 Free Software Foundation, Inc.
 #
 # This file is free software; the Free Software Foundation
 # gives unlimited permission to copy and/or distribute it,
diff --git a/build-aux/missing b/build-aux/missing
index 1c8ff70..f62bbae 100755
--- a/build-aux/missing
+++ b/build-aux/missing
@@ -1,11 +1,10 @@
 #! /bin/sh
-# Common stub for a few missing GNU programs while installing.
+# Common wrapper for a few potentially missing GNU programs.
 
-scriptversion=2006-05-10.23
+scriptversion=2013-10-28.13; # UTC
 
-# Copyright (C) 1996, 1997, 1999, 2000, 2002, 2003, 2004, 2005, 2006
-#   Free Software Foundation, Inc.
-# Originally by Fran,cois Pinard <pinard@iro.umontreal.ca>, 1996.
+# Copyright (C) 1996-2014 Free Software Foundation, Inc.
+# Originally written by Fran,cois Pinard <pinard@iro.umontreal.ca>, 1996.
 
 # 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
@@ -18,9 +17,7 @@ scriptversion=2006-05-10.23
 # 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, write to the Free Software
-# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
-# 02110-1301, USA.
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
 
 # As a special exception to the GNU General Public License, if you
 # distribute this file as part of a program that contains a
@@ -28,66 +25,40 @@ scriptversion=2006-05-10.23
 # the same distribution terms that you use for the rest of that program.
 
 if test $# -eq 0; then
-  echo 1>&2 "Try \`$0 --help' for more information"
+  echo 1>&2 "Try '$0 --help' for more information"
   exit 1
 fi
 
-run=:
-sed_output='s/.* --output[ =]\([^ ]*\).*/\1/p'
-sed_minuso='s/.* -o \([^ ]*\).*/\1/p'
-
-# In the cases where this matters, `missing' is being run in the
-# srcdir already.
-if test -f configure.ac; then
-  configure_ac=configure.ac
-else
-  configure_ac=configure.in
-fi
+case $1 in
 
-msg="missing on your system"
+  --is-lightweight)
+    # Used by our autoconf macros to check whether the available missing
+    # script is modern enough.
+    exit 0
+    ;;
 
-case $1 in
---run)
-  # Try to run requested program, and just exit if it succeeds.
-  run=
-  shift
-  "$@" && exit 0
-  # Exit code 63 means version mismatch.  This often happens
-  # when the user try to use an ancient version of a tool on
-  # a file that requires a minimum version.  In this case we
-  # we should proceed has if the program had been absent, or
-  # if --run hadn't been passed.
-  if test $? = 63; then
-    run=:
-    msg="probably too old"
-  fi
-  ;;
+  --run)
+    # Back-compat with the calling convention used by older automake.
+    shift
+    ;;
 
   -h|--h|--he|--hel|--help)
     echo "\
 $0 [OPTION]... PROGRAM [ARGUMENT]...
 
-Handle \`PROGRAM [ARGUMENT]...' for when PROGRAM is missing, or return an
-error status if there is no known handling for PROGRAM.
+Run 'PROGRAM [ARGUMENT]...', returning a proper advice when this fails due
+to PROGRAM being missing or too old.
 
 Options:
   -h, --help      display this help and exit
   -v, --version   output version information and exit
-  --run           try to run the given command, and emulate it if it fails
 
 Supported PROGRAM values:
-  aclocal      touch file \`aclocal.m4'
-  autoconf     touch file \`configure'
-  autoheader   touch file \`config.h.in'
-  autom4te     touch the output file, or create a stub one
-  automake     touch all \`Makefile.in' files
-  bison        create \`y.tab.[ch]', if possible, from existing .[ch]
-  flex         create \`lex.yy.c', if possible, from existing .c
-  help2man     touch the output file
-  lex          create \`lex.yy.c', if possible, from existing .c
-  makeinfo     touch the output file
-  tar          try tar, gnutar, gtar, then tar without non-portable flags
-  yacc         create \`y.tab.[ch]', if possible, from existing .[ch]
+  aclocal   autoconf  autoheader   autom4te  automake  makeinfo
+  bison     yacc      flex         lex       help2man
+
+Version suffixes to PROGRAM as well as the prefixes 'gnu-', 'gnu', and
+'g' are ignored when checking the name.
 
 Send bug reports to <bug-automake@gnu.org>."
     exit $?
@@ -99,269 +70,146 @@ Send bug reports to <bug-automake@gnu.org>."
     ;;
 
   -*)
-    echo 1>&2 "$0: Unknown \`$1' option"
-    echo 1>&2 "Try \`$0 --help' for more information"
+    echo 1>&2 "$0: unknown '$1' option"
+    echo 1>&2 "Try '$0 --help' for more information"
     exit 1
     ;;
 
 esac
 
-# Now exit if we have it, but it failed.  Also exit now if we
-# don't have it and --version was passed (most likely to detect
-# the program).
-case $1 in
-  lex|yacc)
-    # Not GNU programs, they don't have --version.
-    ;;
-
-  tar)
-    if test -n "$run"; then
-       echo 1>&2 "ERROR: \`tar' requires --run"
-       exit 1
-    elif test "x$2" = "x--version" || test "x$2" = "x--help"; then
-       exit 1
-    fi
-    ;;
-
-  *)
-    if test -z "$run" && ($1 --version) > /dev/null 2>&1; then
-       # We have it, but it failed.
-       exit 1
-    elif test "x$2" = "x--version" || test "x$2" = "x--help"; then
-       # Could not run --version or --help.  This is probably someone
-       # running `$TOOL --version' or `$TOOL --help' to check whether
-       # $TOOL exists and not knowing $TOOL uses missing.
-       exit 1
-    fi
-    ;;
-esac
-
-# If it does not exist, or fails to run (possibly an outdated version),
-# try to emulate it.
-case $1 in
-  aclocal*)
-    echo 1>&2 "\
-WARNING: \`$1' is $msg.  You should only need it if
-         you modified \`acinclude.m4' or \`${configure_ac}'.  You might want
-         to install the \`Automake' and \`Perl' packages.  Grab them from
-         any GNU archive site."
-    touch aclocal.m4
-    ;;
-
-  autoconf)
-    echo 1>&2 "\
-WARNING: \`$1' is $msg.  You should only need it if
-         you modified \`${configure_ac}'.  You might want to install the
-         \`Autoconf' and \`GNU m4' packages.  Grab them from any GNU
-         archive site."
-    touch configure
-    ;;
-
-  autoheader)
-    echo 1>&2 "\
-WARNING: \`$1' is $msg.  You should only need it if
-         you modified \`acconfig.h' or \`${configure_ac}'.  You might want
-         to install the \`Autoconf' and \`GNU m4' packages.  Grab them
-         from any GNU archive site."
-    files=`sed -n 's/^[ ]*A[CM]_CONFIG_HEADER(\([^)]*\)).*/\1/p' ${configure_ac}`
-    test -z "$files" && files="config.h"
-    touch_files=
-    for f in $files; do
-      case $f in
-      *:*) touch_files="$touch_files "`echo "$f" |
-				       sed -e 's/^[^:]*://' -e 's/:.*//'`;;
-      *) touch_files="$touch_files $f.in";;
-      esac
-    done
-    touch $touch_files
-    ;;
-
-  automake*)
-    echo 1>&2 "\
-WARNING: \`$1' is $msg.  You should only need it if
-         you modified \`Makefile.am', \`acinclude.m4' or \`${configure_ac}'.
-         You might want to install the \`Automake' and \`Perl' packages.
-         Grab them from any GNU archive site."
-    find . -type f -name Makefile.am -print |
-	   sed 's/\.am$/.in/' |
-	   while read f; do touch "$f"; done
-    ;;
-
-  autom4te)
-    echo 1>&2 "\
-WARNING: \`$1' is needed, but is $msg.
-         You might have modified some files without having the
-         proper tools for further handling them.
-         You can get \`$1' as part of \`Autoconf' from any GNU
-         archive site."
-
-    file=`echo "$*" | sed -n "$sed_output"`
-    test -z "$file" && file=`echo "$*" | sed -n "$sed_minuso"`
-    if test -f "$file"; then
-	touch $file
-    else
-	test -z "$file" || exec >$file
-	echo "#! /bin/sh"
-	echo "# Created by GNU Automake missing as a replacement of"
-	echo "#  $ $@"
-	echo "exit 0"
-	chmod +x $file
-	exit 1
-    fi
-    ;;
-
-  bison|yacc)
-    echo 1>&2 "\
-WARNING: \`$1' $msg.  You should only need it if
-         you modified a \`.y' file.  You may need the \`Bison' package
-         in order for those modifications to take effect.  You can get
-         \`Bison' from any GNU archive site."
-    rm -f y.tab.c y.tab.h
-    if test $# -ne 1; then
-        eval LASTARG="\${$#}"
-	case $LASTARG in
-	*.y)
-	    SRCFILE=`echo "$LASTARG" | sed 's/y$/c/'`
-	    if test -f "$SRCFILE"; then
-	         cp "$SRCFILE" y.tab.c
-	    fi
-	    SRCFILE=`echo "$LASTARG" | sed 's/y$/h/'`
-	    if test -f "$SRCFILE"; then
-	         cp "$SRCFILE" y.tab.h
-	    fi
-	  ;;
-	esac
-    fi
-    if test ! -f y.tab.h; then
-	echo >y.tab.h
-    fi
-    if test ! -f y.tab.c; then
-	echo 'main() { return 0; }' >y.tab.c
-    fi
-    ;;
-
-  lex|flex)
-    echo 1>&2 "\
-WARNING: \`$1' is $msg.  You should only need it if
-         you modified a \`.l' file.  You may need the \`Flex' package
-         in order for those modifications to take effect.  You can get
-         \`Flex' from any GNU archive site."
-    rm -f lex.yy.c
-    if test $# -ne 1; then
-        eval LASTARG="\${$#}"
-	case $LASTARG in
-	*.l)
-	    SRCFILE=`echo "$LASTARG" | sed 's/l$/c/'`
-	    if test -f "$SRCFILE"; then
-	         cp "$SRCFILE" lex.yy.c
-	    fi
-	  ;;
-	esac
-    fi
-    if test ! -f lex.yy.c; then
-	echo 'main() { return 0; }' >lex.yy.c
-    fi
-    ;;
-
-  help2man)
-    echo 1>&2 "\
-WARNING: \`$1' is $msg.  You should only need it if
-	 you modified a dependency of a manual page.  You may need the
-	 \`Help2man' package in order for those modifications to take
-	 effect.  You can get \`Help2man' from any GNU archive site."
-
-    file=`echo "$*" | sed -n "$sed_output"`
-    test -z "$file" && file=`echo "$*" | sed -n "$sed_minuso"`
-    if test -f "$file"; then
-	touch $file
-    else
-	test -z "$file" || exec >$file
-	echo ".ab help2man is required to generate this page"
-	exit 1
-    fi
-    ;;
-
-  makeinfo)
-    echo 1>&2 "\
-WARNING: \`$1' is $msg.  You should only need it if
-         you modified a \`.texi' or \`.texinfo' file, or any other file
-         indirectly affecting the aspect of the manual.  The spurious
-         call might also be the consequence of using a buggy \`make' (AIX,
-         DU, IRIX).  You might want to install the \`Texinfo' package or
-         the \`GNU make' package.  Grab either from any GNU archive site."
-    # The file to touch is that specified with -o ...
-    file=`echo "$*" | sed -n "$sed_output"`
-    test -z "$file" && file=`echo "$*" | sed -n "$sed_minuso"`
-    if test -z "$file"; then
-      # ... or it is the one specified with @setfilename ...
-      infile=`echo "$*" | sed 's/.* \([^ ]*\) *$/\1/'`
-      file=`sed -n '
-	/^@setfilename/{
-	  s/.* \([^ ]*\) *$/\1/
-	  p
-	  q
-	}' $infile`
-      # ... or it is derived from the source name (dir/f.texi becomes f.info)
-      test -z "$file" && file=`echo "$infile" | sed 's,.*/,,;s,.[^.]*$,,'`.info
-    fi
-    # If the file does not exist, the user really needs makeinfo;
-    # let's fail without touching anything.
-    test -f $file || exit 1
-    touch $file
-    ;;
-
-  tar)
-    shift
-
-    # We have already tried tar in the generic part.
-    # Look for gnutar/gtar before invocation to avoid ugly error
-    # messages.
-    if (gnutar --version > /dev/null 2>&1); then
-       gnutar "$@" && exit 0
-    fi
-    if (gtar --version > /dev/null 2>&1); then
-       gtar "$@" && exit 0
-    fi
-    firstarg="$1"
-    if shift; then
-	case $firstarg in
-	*o*)
-	    firstarg=`echo "$firstarg" | sed s/o//`
-	    tar "$firstarg" "$@" && exit 0
-	    ;;
-	esac
-	case $firstarg in
-	*h*)
-	    firstarg=`echo "$firstarg" | sed s/h//`
-	    tar "$firstarg" "$@" && exit 0
-	    ;;
-	esac
-    fi
-
-    echo 1>&2 "\
-WARNING: I can't seem to be able to run \`tar' with the given arguments.
-         You may want to install GNU tar or Free paxutils, or check the
-         command line arguments."
-    exit 1
-    ;;
-
-  *)
-    echo 1>&2 "\
-WARNING: \`$1' is needed, and is $msg.
-         You might have modified some files without having the
-         proper tools for further handling them.  Check the \`README' file,
-         it often tells you about the needed prerequisites for installing
-         this package.  You may also peek at any GNU archive site, in case
-         some other package would contain this missing \`$1' program."
-    exit 1
-    ;;
-esac
+# Run the given program, remember its exit status.
+"$@"; st=$?
+
+# If it succeeded, we are done.
+test $st -eq 0 && exit 0
+
+# Also exit now if we it failed (or wasn't found), and '--version' was
+# passed; such an option is passed most likely to detect whether the
+# program is present and works.
+case $2 in --version|--help) exit $st;; esac
+
+# Exit code 63 means version mismatch.  This often happens when the user
+# tries to use an ancient version of a tool on a file that requires a
+# minimum version.
+if test $st -eq 63; then
+  msg="probably too old"
+elif test $st -eq 127; then
+  # Program was missing.
+  msg="missing on your system"
+else
+  # Program was found and executed, but failed.  Give up.
+  exit $st
+fi
 
-exit 0
+perl_URL=http://www.perl.org/
+flex_URL=http://flex.sourceforge.net/
+gnu_software_URL=http://www.gnu.org/software
+
+program_details ()
+{
+  case $1 in
+    aclocal|automake)
+      echo "The '$1' program is part of the GNU Automake package:"
+      echo "<$gnu_software_URL/automake>"
+      echo "It also requires GNU Autoconf, GNU m4 and Perl in order to run:"
+      echo "<$gnu_software_URL/autoconf>"
+      echo "<$gnu_software_URL/m4/>"
+      echo "<$perl_URL>"
+      ;;
+    autoconf|autom4te|autoheader)
+      echo "The '$1' program is part of the GNU Autoconf package:"
+      echo "<$gnu_software_URL/autoconf/>"
+      echo "It also requires GNU m4 and Perl in order to run:"
+      echo "<$gnu_software_URL/m4/>"
+      echo "<$perl_URL>"
+      ;;
+  esac
+}
+
+give_advice ()
+{
+  # Normalize program name to check for.
+  normalized_program=`echo "$1" | sed '
+    s/^gnu-//; t
+    s/^gnu//; t
+    s/^g//; t'`
+
+  printf '%s\n' "'$1' is $msg."
+
+  configure_deps="'configure.ac' or m4 files included by 'configure.ac'"
+  case $normalized_program in
+    autoconf*)
+      echo "You should only need it if you modified 'configure.ac',"
+      echo "or m4 files included by it."
+      program_details 'autoconf'
+      ;;
+    autoheader*)
+      echo "You should only need it if you modified 'acconfig.h' or"
+      echo "$configure_deps."
+      program_details 'autoheader'
+      ;;
+    automake*)
+      echo "You should only need it if you modified 'Makefile.am' or"
+      echo "$configure_deps."
+      program_details 'automake'
+      ;;
+    aclocal*)
+      echo "You should only need it if you modified 'acinclude.m4' or"
+      echo "$configure_deps."
+      program_details 'aclocal'
+      ;;
+   autom4te*)
+      echo "You might have modified some maintainer files that require"
+      echo "the 'autom4te' program to be rebuilt."
+      program_details 'autom4te'
+      ;;
+    bison*|yacc*)
+      echo "You should only need it if you modified a '.y' file."
+      echo "You may want to install the GNU Bison package:"
+      echo "<$gnu_software_URL/bison/>"
+      ;;
+    lex*|flex*)
+      echo "You should only need it if you modified a '.l' file."
+      echo "You may want to install the Fast Lexical Analyzer package:"
+      echo "<$flex_URL>"
+      ;;
+    help2man*)
+      echo "You should only need it if you modified a dependency" \
+           "of a man page."
+      echo "You may want to install the GNU Help2man package:"
+      echo "<$gnu_software_URL/help2man/>"
+    ;;
+    makeinfo*)
+      echo "You should only need it if you modified a '.texi' file, or"
+      echo "any other file indirectly affecting the aspect of the manual."
+      echo "You might want to install the Texinfo package:"
+      echo "<$gnu_software_URL/texinfo/>"
+      echo "The spurious makeinfo call might also be the consequence of"
+      echo "using a buggy 'make' (AIX, DU, IRIX), in which case you might"
+      echo "want to install GNU make:"
+      echo "<$gnu_software_URL/make/>"
+      ;;
+    *)
+      echo "You might have modified some files without having the proper"
+      echo "tools for further handling them.  Check the 'README' file, it"
+      echo "often tells you about the needed prerequisites for installing"
+      echo "this package.  You may also peek at any GNU archive site, in"
+      echo "case some other package contains this missing '$1' program."
+      ;;
+  esac
+}
+
+give_advice "$1" | sed -e '1s/^/WARNING: /' \
+                       -e '2,$s/^/         /' >&2
+
+# Propagate the correct exit status (expected to be 127 for a program
+# not found, 63 for a program that failed due to version mismatch).
+exit $st
 
 # Local variables:
 # eval: (add-hook 'write-file-hooks 'time-stamp)
 # time-stamp-start: "scriptversion="
 # time-stamp-format: "%:y-%02m-%02d.%02H"
-# time-stamp-end: "$"
+# time-stamp-time-zone: "UTC"
+# time-stamp-end: "; # UTC"
 # End:
diff --git a/configure b/configure
index 1d8288a..16a316f 100755
--- a/configure
+++ b/configure
@@ -1,8 +1,8 @@
 #! /bin/sh
 # Guess values for system-dependent variables and create Makefiles.
-# Generated by GNU Autoconf 2.69 for mandelSSE 2.0.
+# Generated by GNU Autoconf 2.69 for mandelSSE 2.1.
 #
-# Report bugs to <ttsiod@softlab.ntua.gr>.
+# Report bugs to <ttsiodras@gmail.com>.
 #
 #
 # Copyright (C) 1992-1996, 1998-2012 Free Software Foundation, Inc.
@@ -267,7 +267,7 @@ fi
     $as_echo "$0: be upgraded to zsh 4.3.4 or later."
   else
     $as_echo "$0: Please tell bug-autoconf@gnu.org and
-$0: ttsiod@softlab.ntua.gr about your system, including any
+$0: ttsiodras@gmail.com about your system, including any
 $0: error possibly output before this message. Then install
 $0: a modern shell, or manually run the script under such a
 $0: shell if you do have one."
@@ -580,9 +580,9 @@ MAKEFLAGS=
 # Identity of this package.
 PACKAGE_NAME='mandelSSE'
 PACKAGE_TARNAME='mandelsse'
-PACKAGE_VERSION='2.0'
-PACKAGE_STRING='mandelSSE 2.0'
-PACKAGE_BUGREPORT='ttsiod@softlab.ntua.gr'
+PACKAGE_VERSION='2.1'
+PACKAGE_STRING='mandelSSE 2.1'
+PACKAGE_BUGREPORT='ttsiodras@gmail.com'
 PACKAGE_URL=''
 
 # Factoring default headers for most tests.
@@ -639,6 +639,7 @@ am__nodep
 AMDEPBACKSLASH
 AMDEP_FALSE
 AMDEP_TRUE
+am__quote
 am__include
 DEPDIR
 OBJEXT
@@ -687,6 +688,9 @@ build_os
 build_vendor
 build_cpu
 build
+LAST_CONFIG_YEAR
+LAST_CONFIG_DATE
+SCM_REVISION
 target_alias
 host_alias
 build_alias
@@ -706,6 +710,7 @@ infodir
 docdir
 oldincludedir
 includedir
+runstatedir
 localstatedir
 sharedstatedir
 sysconfdir
@@ -724,8 +729,7 @@ PACKAGE_VERSION
 PACKAGE_TARNAME
 PACKAGE_NAME
 PATH_SEPARATOR
-SHELL
-am__quote'
+SHELL'
 ac_subst_files=''
 ac_user_opts='
 enable_option_checking
@@ -787,6 +791,7 @@ datadir='${datarootdir}'
 sysconfdir='${prefix}/etc'
 sharedstatedir='${prefix}/com'
 localstatedir='${prefix}/var'
+runstatedir='${localstatedir}/run'
 includedir='${prefix}/include'
 oldincludedir='/usr/include'
 docdir='${datarootdir}/doc/${PACKAGE_TARNAME}'
@@ -1039,6 +1044,15 @@ do
   | -silent | --silent | --silen | --sile | --sil)
     silent=yes ;;
 
+  -runstatedir | --runstatedir | --runstatedi | --runstated \
+  | --runstate | --runstat | --runsta | --runst | --runs \
+  | --run | --ru | --r)
+    ac_prev=runstatedir ;;
+  -runstatedir=* | --runstatedir=* | --runstatedi=* | --runstated=* \
+  | --runstate=* | --runstat=* | --runsta=* | --runst=* | --runs=* \
+  | --run=* | --ru=* | --r=*)
+    runstatedir=$ac_optarg ;;
+
   -sbindir | --sbindir | --sbindi | --sbind | --sbin | --sbi | --sb)
     ac_prev=sbindir ;;
   -sbindir=* | --sbindir=* | --sbindi=* | --sbind=* | --sbin=* \
@@ -1176,7 +1190,7 @@ fi
 for ac_var in	exec_prefix prefix bindir sbindir libexecdir datarootdir \
 		datadir sysconfdir sharedstatedir localstatedir includedir \
 		oldincludedir docdir infodir htmldir dvidir pdfdir psdir \
-		libdir localedir mandir
+		libdir localedir mandir runstatedir
 do
   eval ac_val=\$$ac_var
   # Remove trailing slashes.
@@ -1289,7 +1303,7 @@ if test "$ac_init_help" = "long"; then
   # Omit some internal or obsolete options to make the list less imposing.
   # This message is too long to be a string in the A/UX 3.1 sh.
   cat <<_ACEOF
-\`configure' configures mandelSSE 2.0 to adapt to many kinds of systems.
+\`configure' configures mandelSSE 2.1 to adapt to many kinds of systems.
 
 Usage: $0 [OPTION]... [VAR=VALUE]...
 
@@ -1329,6 +1343,7 @@ Fine tuning of the installation directories:
   --sysconfdir=DIR        read-only single-machine data [PREFIX/etc]
   --sharedstatedir=DIR    modifiable architecture-independent data [PREFIX/com]
   --localstatedir=DIR     modifiable single-machine data [PREFIX/var]
+  --runstatedir=DIR       modifiable per-process data [LOCALSTATEDIR/run]
   --libdir=DIR            object code libraries [EPREFIX/lib]
   --includedir=DIR        C header files [PREFIX/include]
   --oldincludedir=DIR     C header files for non-gcc [/usr/include]
@@ -1360,7 +1375,7 @@ fi
 
 if test -n "$ac_init_help"; then
   case $ac_init_help in
-     short | recursive ) echo "Configuration of mandelSSE 2.0:";;
+     short | recursive ) echo "Configuration of mandelSSE 2.1:";;
    esac
   cat <<\_ACEOF
 
@@ -1401,7 +1416,7 @@ Some influential environment variables:
 Use these variables to override the choices made by `configure' or to help
 it to find libraries and programs with nonstandard names/locations.
 
-Report bugs to <ttsiod@softlab.ntua.gr>.
+Report bugs to <ttsiodras@gmail.com>.
 _ACEOF
 ac_status=$?
 fi
@@ -1464,7 +1479,7 @@ fi
 test -n "$ac_init_help" && exit $ac_status
 if $ac_init_version; then
   cat <<\_ACEOF
-mandelSSE configure 2.0
+mandelSSE configure 2.1
 generated by GNU Autoconf 2.69
 
 Copyright (C) 2012 Free Software Foundation, Inc.
@@ -1778,9 +1793,9 @@ $as_echo "$as_me: WARNING: $2: see the Autoconf documentation" >&2;}
 $as_echo "$as_me: WARNING: $2:     section \"Present But Cannot Be Compiled\"" >&2;}
     { $as_echo "$as_me:${as_lineno-$LINENO}: WARNING: $2: proceeding with the compiler's result" >&5
 $as_echo "$as_me: WARNING: $2: proceeding with the compiler's result" >&2;}
-( $as_echo "## ------------------------------------- ##
-## Report this to ttsiod@softlab.ntua.gr ##
-## ------------------------------------- ##"
+( $as_echo "## ---------------------------------- ##
+## Report this to ttsiodras@gmail.com ##
+## ---------------------------------- ##"
      ) | sed "s/^/$as_me: WARNING:     /" >&2
     ;;
 esac
@@ -1833,7 +1848,7 @@ cat >config.log <<_ACEOF
 This file contains any messages produced by compilers while
 running configure, to aid debugging if configure makes a mistake.
 
-It was created by mandelSSE $as_me 2.0, which was
+It was created by mandelSSE $as_me 2.1, which was
 generated by GNU Autoconf 2.69.  Invocation command line was
 
   $ $0 $@
@@ -2193,6 +2208,67 @@ ac_config_headers="$ac_config_headers src/config.h"
 
 
 
+# Take the current SVN revision
+
+{ $as_echo "$as_me:${as_lineno-$LINENO}: checking whether this is a SCM working copy" >&5
+$as_echo_n "checking whether this is a SCM working copy... " >&6; }
+
+temp_scm_output=`(cd $srcdir; git rev-parse --short HEAD)`
+
+if test x"${temp_scm_output}" = x""; then
+   # This means we are NOT working on a repository copy, the value of
+   # SCM_REVISION will not be taken into account.
+
+   SCM_REVISION=""
+   { $as_echo "$as_me:${as_lineno-$LINENO}: result: no." >&5
+$as_echo "no." >&6; }
+else
+   SCM_REVISION="r${temp_scm_output}"
+   { $as_echo "$as_me:${as_lineno-$LINENO}: result: yes: ${SCM_REVISION}." >&5
+$as_echo "yes: ${SCM_REVISION}." >&6; }
+fi
+
+
+
+# Take the configure full date
+
+{ $as_echo "$as_me:${as_lineno-$LINENO}: checking the configuration full date" >&5
+$as_echo_n "checking the configuration full date... " >&6; }
+
+temp_config_date=`LANG=C date +"%A %d %B %Y, %H:%M:%S"`
+
+if test x"${temp_config_date}" = x""; then
+   LAST_CONFIG_DATE=""
+   { $as_echo "$as_me:${as_lineno-$LINENO}: result: empty date." >&5
+$as_echo "empty date." >&6; }
+else
+   LAST_CONFIG_DATE="${temp_config_date}"
+   { $as_echo "$as_me:${as_lineno-$LINENO}: result: ${LAST_CONFIG_DATE}." >&5
+$as_echo "${LAST_CONFIG_DATE}." >&6; }
+fi
+
+
+
+# Take the configure year
+
+{ $as_echo "$as_me:${as_lineno-$LINENO}: checking the configuration year" >&5
+$as_echo_n "checking the configuration year... " >&6; }
+
+temp_config_year=`LANG=C date +"%Y"`
+
+if test x"${temp_config_year}" = x""; then
+   LAST_CONFIG_YEAR="2007"
+   { $as_echo "$as_me:${as_lineno-$LINENO}: result: no year found" >&5
+$as_echo "no year found" >&6; }
+else
+   LAST_CONFIG_YEAR="${temp_config_year}"
+   { $as_echo "$as_me:${as_lineno-$LINENO}: result: ${LAST_CONFIG_YEAR}" >&5
+$as_echo "${LAST_CONFIG_YEAR}" >&6; }
+fi
+
+
+
+
 # Don't clutter this dir, store in build-aux
 ac_aux_dir=
 for ac_dir in build-aux "$srcdir"/build-aux; do
@@ -2340,7 +2416,7 @@ test -n "$target_alias" &&
     NONENONEs,x,x, &&
   program_prefix=${target_alias}-
 
-am__api_version='1.16'
+am__api_version='1.15'
 
 # Find a good install program.  We prefer a C program (faster),
 # so one script is as good as another.  But avoid the broken or
@@ -2826,7 +2902,7 @@ fi
 
 # Define the identity of the package.
  PACKAGE='mandelsse'
- VERSION='2.0'
+ VERSION='2.1'
 
 
 cat >>confdefs.h <<_ACEOF
@@ -2856,8 +2932,8 @@ MAKEINFO=${MAKEINFO-"${am_missing_run}makeinfo"}
 
 # For better backward compatibility.  To be removed once Automake 1.9.x
 # dies out for good.  For more background, see:
-# <https://lists.gnu.org/archive/html/automake/2012-07/msg00001.html>
-# <https://lists.gnu.org/archive/html/automake/2012-07/msg00014.html>
+# <http://lists.gnu.org/archive/html/automake/2012-07/msg00001.html>
+# <http://lists.gnu.org/archive/html/automake/2012-07/msg00014.html>
 mkdir_p='$(MKDIR_P)'
 
 # We need awk for the "check" target (and possibly the TAP driver).  The
@@ -2908,7 +2984,7 @@ END
 Aborting the configuration process, to ensure you take notice of the issue.
 
 You can download and install GNU coreutils to get an 'rm' implementation
-that behaves properly: <https://www.gnu.org/software/coreutils/>.
+that behaves properly: <http://www.gnu.org/software/coreutils/>.
 
 If you want to complete the configuration process using your problematic
 'rm' anyway, export the environment variable ACCEPT_INFERIOR_RM_PROGRAM
@@ -3003,45 +3079,45 @@ DEPDIR="${am__leading_dot}deps"
 
 ac_config_commands="$ac_config_commands depfiles"
 
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking whether ${MAKE-make} supports the include directive" >&5
-$as_echo_n "checking whether ${MAKE-make} supports the include directive... " >&6; }
-cat > confinc.mk << 'END'
+
+am_make=${MAKE-make}
+cat > confinc << 'END'
 am__doit:
-	@echo this is the am__doit target >confinc.out
+	@echo this is the am__doit target
 .PHONY: am__doit
 END
+# If we don't find an include directive, just comment out the code.
+{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for style of include used by $am_make" >&5
+$as_echo_n "checking for style of include used by $am_make... " >&6; }
 am__include="#"
 am__quote=
-# BSD make does it like this.
-echo '.include "confinc.mk" # ignored' > confmf.BSD
-# Other make implementations (GNU, Solaris 10, AIX) do it like this.
-echo 'include confinc.mk # ignored' > confmf.GNU
-_am_result=no
-for s in GNU BSD; do
-  { echo "$as_me:$LINENO: ${MAKE-make} -f confmf.$s && cat confinc.out" >&5
-   (${MAKE-make} -f confmf.$s && cat confinc.out) >&5 2>&5
-   ac_status=$?
-   echo "$as_me:$LINENO: \$? = $ac_status" >&5
-   (exit $ac_status); }
-  case $?:`cat confinc.out 2>/dev/null` in #(
-  '0:this is the am__doit target') :
-    case $s in #(
-  BSD) :
-    am__include='.include' am__quote='"' ;; #(
-  *) :
-    am__include='include' am__quote='' ;;
-esac ;; #(
-  *) :
-     ;;
+_am_result=none
+# First try GNU make style include.
+echo "include confinc" > confmf
+# Ignore all kinds of additional output from 'make'.
+case `$am_make -s -f confmf 2> /dev/null` in #(
+*the\ am__doit\ target*)
+  am__include=include
+  am__quote=
+  _am_result=GNU
+  ;;
 esac
-  if test "$am__include" != "#"; then
-    _am_result="yes ($s style)"
-    break
-  fi
-done
-rm -f confinc.* confmf.*
-{ $as_echo "$as_me:${as_lineno-$LINENO}: result: ${_am_result}" >&5
-$as_echo "${_am_result}" >&6; }
+# Now try BSD make style include.
+if test "$am__include" = "#"; then
+   echo '.include "confinc"' > confmf
+   case `$am_make -s -f confmf 2> /dev/null` in #(
+   *the\ am__doit\ target*)
+     am__include=.include
+     am__quote="\""
+     _am_result=BSD
+     ;;
+   esac
+fi
+
+
+{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $_am_result" >&5
+$as_echo "$_am_result" >&6; }
+rm -f confinc confmf
 
 # Check whether --enable-dependency-tracking was given.
 if test "${enable_dependency_tracking+set}" = set; then :
@@ -5862,7 +5938,7 @@ rm -f core conftest.err conftest.$ac_objext \
 
 
 # Finally create all the generated files
-ac_config_files="$ac_config_files Makefile src/Makefile"
+ac_config_files="$ac_config_files Makefile src/Makefile src/version.h"
 
 cat >confcache <<\_ACEOF
 # This file is a shell script that caches the results of configure
@@ -6394,7 +6470,7 @@ cat >>$CONFIG_STATUS <<\_ACEOF || ac_write_fail=1
 # report actual input values of CONFIG_FILES etc. instead of their
 # values after options handling.
 ac_log="
-This file was extended by mandelSSE $as_me 2.0, which was
+This file was extended by mandelSSE $as_me 2.1, which was
 generated by GNU Autoconf 2.69.  Invocation command line was
 
   CONFIG_FILES    = $CONFIG_FILES
@@ -6454,13 +6530,13 @@ $config_headers
 Configuration commands:
 $config_commands
 
-Report bugs to <ttsiod@softlab.ntua.gr>."
+Report bugs to <ttsiodras@gmail.com>."
 
 _ACEOF
 cat >>$CONFIG_STATUS <<_ACEOF || ac_write_fail=1
 ac_cs_config="`$as_echo "$ac_configure_args" | sed 's/^ //; s/[\\""\`\$]/\\\\&/g'`"
 ac_cs_version="\\
-mandelSSE config.status 2.0
+mandelSSE config.status 2.1
 configured by $0, generated by GNU Autoconf 2.69,
   with options \\"\$ac_cs_config\\"
 
@@ -6579,7 +6655,7 @@ cat >>$CONFIG_STATUS <<_ACEOF || ac_write_fail=1
 #
 # INIT-COMMANDS
 #
-AMDEP_TRUE="$AMDEP_TRUE" MAKE="${MAKE-make}"
+AMDEP_TRUE="$AMDEP_TRUE" ac_aux_dir="$ac_aux_dir"
 
 _ACEOF
 
@@ -6593,6 +6669,7 @@ do
     "depfiles") CONFIG_COMMANDS="$CONFIG_COMMANDS depfiles" ;;
     "Makefile") CONFIG_FILES="$CONFIG_FILES Makefile" ;;
     "src/Makefile") CONFIG_FILES="$CONFIG_FILES src/Makefile" ;;
+    "src/version.h") CONFIG_FILES="$CONFIG_FILES src/version.h" ;;
 
   *) as_fn_error $? "invalid argument: \`$ac_config_target'" "$LINENO" 5;;
   esac
@@ -7192,35 +7269,29 @@ $as_echo "$as_me: executing $ac_file commands" >&6;}
   # Older Autoconf quotes --file arguments for eval, but not when files
   # are listed without --file.  Let's play safe and only enable the eval
   # if we detect the quoting.
-  # TODO: see whether this extra hack can be removed once we start
-  # requiring Autoconf 2.70 or later.
-  case $CONFIG_FILES in #(
-  *\'*) :
-    eval set x "$CONFIG_FILES" ;; #(
-  *) :
-    set x $CONFIG_FILES ;; #(
-  *) :
-     ;;
-esac
+  case $CONFIG_FILES in
+  *\'*) eval set x "$CONFIG_FILES" ;;
+  *)   set x $CONFIG_FILES ;;
+  esac
   shift
-  # Used to flag and report bootstrapping failures.
-  am_rc=0
-  for am_mf
+  for mf
   do
     # Strip MF so we end up with the name of the file.
-    am_mf=`$as_echo "$am_mf" | sed -e 's/:.*$//'`
-    # Check whether this is an Automake generated Makefile which includes
-    # dependency-tracking related rules and includes.
-    # Grep'ing the whole file directly is not great: AIX grep has a line
+    mf=`echo "$mf" | sed -e 's/:.*$//'`
+    # Check whether this is an Automake generated Makefile or not.
+    # We used to match only the files named 'Makefile.in', but
+    # some people rename them; so instead we look at the file content.
+    # Grep'ing the first line is not enough: some people post-process
+    # each Makefile.in and add a new line on top of each file to say so.
+    # Grep'ing the whole file is not good either: AIX grep has a line
     # limit of 2048, but all sed's we know have understand at least 4000.
-    sed -n 's,^am--depfiles:.*,X,p' "$am_mf" | grep X >/dev/null 2>&1 \
-      || continue
-    am_dirpart=`$as_dirname -- "$am_mf" ||
-$as_expr X"$am_mf" : 'X\(.*[^/]\)//*[^/][^/]*/*$' \| \
-	 X"$am_mf" : 'X\(//\)[^/]' \| \
-	 X"$am_mf" : 'X\(//\)$' \| \
-	 X"$am_mf" : 'X\(/\)' \| . 2>/dev/null ||
-$as_echo X"$am_mf" |
+    if sed -n 's,^#.*generated by automake.*,X,p' "$mf" | grep X >/dev/null 2>&1; then
+      dirpart=`$as_dirname -- "$mf" ||
+$as_expr X"$mf" : 'X\(.*[^/]\)//*[^/][^/]*/*$' \| \
+	 X"$mf" : 'X\(//\)[^/]' \| \
+	 X"$mf" : 'X\(//\)$' \| \
+	 X"$mf" : 'X\(/\)' \| . 2>/dev/null ||
+$as_echo X"$mf" |
     sed '/^X\(.*[^/]\)\/\/*[^/][^/]*\/*$/{
 	    s//\1/
 	    q
@@ -7238,50 +7309,53 @@ $as_echo X"$am_mf" |
 	    q
 	  }
 	  s/.*/./; q'`
-    am_filepart=`$as_basename -- "$am_mf" ||
-$as_expr X/"$am_mf" : '.*/\([^/][^/]*\)/*$' \| \
-	 X"$am_mf" : 'X\(//\)$' \| \
-	 X"$am_mf" : 'X\(/\)' \| . 2>/dev/null ||
-$as_echo X/"$am_mf" |
-    sed '/^.*\/\([^/][^/]*\)\/*$/{
+    else
+      continue
+    fi
+    # Extract the definition of DEPDIR, am__include, and am__quote
+    # from the Makefile without running 'make'.
+    DEPDIR=`sed -n 's/^DEPDIR = //p' < "$mf"`
+    test -z "$DEPDIR" && continue
+    am__include=`sed -n 's/^am__include = //p' < "$mf"`
+    test -z "$am__include" && continue
+    am__quote=`sed -n 's/^am__quote = //p' < "$mf"`
+    # Find all dependency output files, they are included files with
+    # $(DEPDIR) in their names.  We invoke sed twice because it is the
+    # simplest approach to changing $(DEPDIR) to its actual value in the
+    # expansion.
+    for file in `sed -n "
+      s/^$am__include $am__quote\(.*(DEPDIR).*\)$am__quote"'$/\1/p' <"$mf" | \
+	 sed -e 's/\$(DEPDIR)/'"$DEPDIR"'/g'`; do
+      # Make sure the directory exists.
+      test -f "$dirpart/$file" && continue
+      fdir=`$as_dirname -- "$file" ||
+$as_expr X"$file" : 'X\(.*[^/]\)//*[^/][^/]*/*$' \| \
+	 X"$file" : 'X\(//\)[^/]' \| \
+	 X"$file" : 'X\(//\)$' \| \
+	 X"$file" : 'X\(/\)' \| . 2>/dev/null ||
+$as_echo X"$file" |
+    sed '/^X\(.*[^/]\)\/\/*[^/][^/]*\/*$/{
 	    s//\1/
 	    q
 	  }
-	  /^X\/\(\/\/\)$/{
+	  /^X\(\/\/\)[^/].*/{
 	    s//\1/
 	    q
 	  }
-	  /^X\/\(\/\).*/{
+	  /^X\(\/\/\)$/{
+	    s//\1/
+	    q
+	  }
+	  /^X\(\/\).*/{
 	    s//\1/
 	    q
 	  }
 	  s/.*/./; q'`
-    { echo "$as_me:$LINENO: cd "$am_dirpart" \
-      && sed -e '/# am--include-marker/d' "$am_filepart" \
-        | $MAKE -f - am--depfiles" >&5
-   (cd "$am_dirpart" \
-      && sed -e '/# am--include-marker/d' "$am_filepart" \
-        | $MAKE -f - am--depfiles) >&5 2>&5
-   ac_status=$?
-   echo "$as_me:$LINENO: \$? = $ac_status" >&5
-   (exit $ac_status); } || am_rc=$?
+      as_dir=$dirpart/$fdir; as_fn_mkdir_p
+      # echo "creating $dirpart/$file"
+      echo '# dummy' > "$dirpart/$file"
+    done
   done
-  if test $am_rc -ne 0; then
-    { { $as_echo "$as_me:${as_lineno-$LINENO}: error: in \`$ac_pwd':" >&5
-$as_echo "$as_me: error: in \`$ac_pwd':" >&2;}
-as_fn_error $? "Something went wrong bootstrapping makefile fragments
-    for automatic dependency tracking.  If GNU make was not used, consider
-    re-running the configure script with MAKE=\"gmake\" (or whatever is
-    necessary).  You can also try re-running configure with the
-    '--disable-dependency-tracking' option to at least be able to build
-    the package (albeit without support for automatic dependency tracking).
-See \`config.log' for more details" "$LINENO" 5; }
-  fi
-  { am_dirpart=; unset am_dirpart;}
-  { am_filepart=; unset am_filepart;}
-  { am_mf=; unset am_mf;}
-  { am_rc=; unset am_rc;}
-  rm -f conftest-deps.mk
 }
  ;;
 
diff --git a/configure.ac b/configure.ac
index ba6873f..03c98bd 100644
--- a/configure.ac
+++ b/configure.ac
@@ -1,9 +1,10 @@
-AC_INIT([mandelSSE], [2.0], [ttsiod@softlab.ntua.gr])
+AC_INIT([mandelSSE], [2.1], [ttsiodras@gmail.com])
 
 AC_LANG(C)
 AC_CONFIG_HEADERS([src/config.h])
 
 AC_CONFIG_MACRO_DIR([ac-macros])
+AM_REVISION_UTILS
 
 # Don't clutter this dir, store in build-aux
 AC_CONFIG_AUX_DIR([build-aux])
@@ -172,5 +173,5 @@ AC_SUBST(SDL_CFLAGS)
 AC_SUBST(SDL_LIBS)
 
 # Finally create all the generated files
-AC_CONFIG_FILES([Makefile src/Makefile]) 
+AC_CONFIG_FILES([Makefile src/Makefile src/version.h]) 
 AC_OUTPUT
diff --git a/src/Makefile.am b/src/Makefile.am
index 85a83c3..842dd79 100644
--- a/src/Makefile.am
+++ b/src/Makefile.am
@@ -1,6 +1,6 @@
 noinst_PROGRAMS = mandelSSE
 
-mandelSSE_SOURCES = mandel.c sse.c xaos.c common.c
+mandelSSE_SOURCES = mandel.c sse.c sse.h xaos.c xaos.h common.c common.h version.h
 
 mandelSSE_CPPFLAGS = @SDL_CFLAGS@
 
diff --git a/src/Makefile.in b/src/Makefile.in
index 6fa2434..5e7fbf9 100644
--- a/src/Makefile.in
+++ b/src/Makefile.in
@@ -1,7 +1,7 @@
-# Makefile.in generated by automake 1.16.2 from Makefile.am.
+# Makefile.in generated by automake 1.15 from Makefile.am.
 # @configure_input@
 
-# Copyright (C) 1994-2020 Free Software Foundation, Inc.
+# Copyright (C) 1994-2014 Free Software Foundation, Inc.
 
 # This Makefile.in is free software; the Free Software Foundation
 # gives unlimited permission to copy and/or distribute it,
@@ -95,13 +95,14 @@ ACLOCAL_M4 = $(top_srcdir)/aclocal.m4
 am__aclocal_m4_deps = $(top_srcdir)/acinclude.m4 \
 	$(top_srcdir)/ac-macros/ax_openmp.m4 \
 	$(top_srcdir)/ac-macros/ax_cflags_gcc_option.m4 \
+	$(top_srcdir)/ac-macros/revision_utils.m4 \
 	$(top_srcdir)/configure.ac
 am__configure_deps = $(am__aclocal_m4_deps) $(CONFIGURE_DEPENDENCIES) \
 	$(ACLOCAL_M4)
 DIST_COMMON = $(srcdir)/Makefile.am $(am__DIST_COMMON)
 mkinstalldirs = $(install_sh) -d
 CONFIG_HEADER = config.h
-CONFIG_CLEAN_FILES =
+CONFIG_CLEAN_FILES = version.h
 CONFIG_CLEAN_VPATH_FILES =
 PROGRAMS = $(noinst_PROGRAMS)
 am_mandelSSE_OBJECTS = mandelSSE-mandel.$(OBJEXT) \
@@ -123,10 +124,7 @@ am__v_at_0 = @
 am__v_at_1 = 
 DEFAULT_INCLUDES = -I.@am__isrc@
 depcomp = $(SHELL) $(top_srcdir)/build-aux/depcomp
-am__maybe_remake_depfiles = depfiles
-am__depfiles_remade = ./$(DEPDIR)/mandelSSE-common.Po \
-	./$(DEPDIR)/mandelSSE-mandel.Po ./$(DEPDIR)/mandelSSE-sse.Po \
-	./$(DEPDIR)/mandelSSE-xaos.Po
+am__depfiles_maybe = depfiles
 am__mv = mv -f
 AM_V_lt = $(am__v_lt_@AM_V@)
 am__v_lt_ = $(am__v_lt_@AM_DEFAULT_V@)
@@ -151,8 +149,8 @@ am__can_run_installinfo = \
     n|no|NO) false;; \
     *) (install-info --version) >/dev/null 2>&1;; \
   esac
-am__tagged_files = $(HEADERS) $(SOURCES) $(TAGS_FILES) $(LISP) \
-	config.h.in
+am__tagged_files = $(HEADERS) $(SOURCES) $(TAGS_FILES) \
+	$(LISP)config.h.in
 # Read a list of newline-separated strings from the standard input,
 # and print each of them once, without duplicates.  Input order is
 # *not* preserved.
@@ -172,7 +170,7 @@ am__define_uniq_tagged_files = \
 ETAGS = etags
 CTAGS = ctags
 am__DIST_COMMON = $(srcdir)/Makefile.in $(srcdir)/config.h.in \
-	$(top_srcdir)/build-aux/depcomp
+	$(srcdir)/version.h.in $(top_srcdir)/build-aux/depcomp
 DISTFILES = $(DIST_COMMON) $(DIST_SOURCES) $(TEXINFOS) $(EXTRA_DIST)
 ACLOCAL = @ACLOCAL@
 AMTAR = @AMTAR@
@@ -200,6 +198,8 @@ INSTALL_DATA = @INSTALL_DATA@
 INSTALL_PROGRAM = @INSTALL_PROGRAM@
 INSTALL_SCRIPT = @INSTALL_SCRIPT@
 INSTALL_STRIP_PROGRAM = @INSTALL_STRIP_PROGRAM@
+LAST_CONFIG_DATE = @LAST_CONFIG_DATE@
+LAST_CONFIG_YEAR = @LAST_CONFIG_YEAR@
 LDFLAGS = @LDFLAGS@
 LIBOBJS = @LIBOBJS@
 LIBS = @LIBS@
@@ -216,6 +216,7 @@ PACKAGE_TARNAME = @PACKAGE_TARNAME@
 PACKAGE_URL = @PACKAGE_URL@
 PACKAGE_VERSION = @PACKAGE_VERSION@
 PATH_SEPARATOR = @PATH_SEPARATOR@
+SCM_REVISION = @SCM_REVISION@
 SDL_CFLAGS = @SDL_CFLAGS@
 SDL_CONFIG = @SDL_CONFIG@
 SDL_LIBS = @SDL_LIBS@
@@ -265,6 +266,7 @@ pdfdir = @pdfdir@
 prefix = @prefix@
 program_transform_name = @program_transform_name@
 psdir = @psdir@
+runstatedir = @runstatedir@
 sbindir = @sbindir@
 sharedstatedir = @sharedstatedir@
 srcdir = @srcdir@
@@ -277,7 +279,7 @@ target_vendor = @target_vendor@
 top_build_prefix = @top_build_prefix@
 top_builddir = @top_builddir@
 top_srcdir = @top_srcdir@
-mandelSSE_SOURCES = mandel.c sse.c xaos.c common.c
+mandelSSE_SOURCES = mandel.c sse.c sse.h xaos.c xaos.h common.c common.h version.h
 mandelSSE_CPPFLAGS = @SDL_CFLAGS@
 mandelSSE_LDADD = @SDL_LIBS@ @OPENMP_LIBS@
 all: config.h
@@ -302,8 +304,8 @@ Makefile: $(srcdir)/Makefile.in $(top_builddir)/config.status
 	  *config.status*) \
 	    cd $(top_builddir) && $(MAKE) $(AM_MAKEFLAGS) am--refresh;; \
 	  *) \
-	    echo ' cd $(top_builddir) && $(SHELL) ./config.status $(subdir)/$@ $(am__maybe_remake_depfiles)'; \
-	    cd $(top_builddir) && $(SHELL) ./config.status $(subdir)/$@ $(am__maybe_remake_depfiles);; \
+	    echo ' cd $(top_builddir) && $(SHELL) ./config.status $(subdir)/$@ $(am__depfiles_maybe)'; \
+	    cd $(top_builddir) && $(SHELL) ./config.status $(subdir)/$@ $(am__depfiles_maybe);; \
 	esac;
 
 $(top_builddir)/config.status: $(top_srcdir)/configure $(CONFIG_STATUS_DEPENDENCIES)
@@ -329,6 +331,8 @@ $(srcdir)/config.h.in:  $(am__configure_deps)
 
 distclean-hdr:
 	-rm -f config.h stamp-h1
+version.h: $(top_builddir)/config.status $(srcdir)/version.h.in
+	cd $(top_builddir) && $(SHELL) ./config.status $(subdir)/$@
 
 clean-noinstPROGRAMS:
 	-test -z "$(noinst_PROGRAMS)" || rm -f $(noinst_PROGRAMS)
@@ -343,16 +347,10 @@ mostlyclean-compile:
 distclean-compile:
 	-rm -f *.tab.c
 
-@AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/mandelSSE-common.Po@am__quote@ # am--include-marker
-@AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/mandelSSE-mandel.Po@am__quote@ # am--include-marker
-@AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/mandelSSE-sse.Po@am__quote@ # am--include-marker
-@AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/mandelSSE-xaos.Po@am__quote@ # am--include-marker
-
-$(am__depfiles_remade):
-	@$(MKDIR_P) $(@D)
-	@echo '# dummy' >$@-t && $(am__mv) $@-t $@
-
-am--depfiles: $(am__depfiles_remade)
+@AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/mandelSSE-common.Po@am__quote@
+@AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/mandelSSE-mandel.Po@am__quote@
+@AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/mandelSSE-sse.Po@am__quote@
+@AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/mandelSSE-xaos.Po@am__quote@
 
 .c.o:
 @am__fastdepCC_TRUE@	$(AM_V_CC)$(COMPILE) -MT $@ -MD -MP -MF $(DEPDIR)/$*.Tpo -c -o $@ $<
@@ -476,10 +474,7 @@ cscopelist-am: $(am__tagged_files)
 distclean-tags:
 	-rm -f TAGS ID GTAGS GRTAGS GSYMS GPATH tags
 
-distdir: $(BUILT_SOURCES)
-	$(MAKE) $(AM_MAKEFLAGS) distdir-am
-
-distdir-am: $(DISTFILES)
+distdir: $(DISTFILES)
 	@srcdirstrip=`echo "$(srcdir)" | sed 's/[].[^$$\\*]/\\\\&/g'`; \
 	topsrcdirstrip=`echo "$(top_srcdir)" | sed 's/[].[^$$\\*]/\\\\&/g'`; \
 	list='$(DISTFILES)'; \
@@ -548,10 +543,7 @@ clean: clean-am
 clean-am: clean-generic clean-noinstPROGRAMS mostlyclean-am
 
 distclean: distclean-am
-		-rm -f ./$(DEPDIR)/mandelSSE-common.Po
-	-rm -f ./$(DEPDIR)/mandelSSE-mandel.Po
-	-rm -f ./$(DEPDIR)/mandelSSE-sse.Po
-	-rm -f ./$(DEPDIR)/mandelSSE-xaos.Po
+	-rm -rf ./$(DEPDIR)
 	-rm -f Makefile
 distclean-am: clean-am distclean-compile distclean-generic \
 	distclean-hdr distclean-tags
@@ -597,10 +589,7 @@ install-ps-am:
 installcheck-am:
 
 maintainer-clean: maintainer-clean-am
-		-rm -f ./$(DEPDIR)/mandelSSE-common.Po
-	-rm -f ./$(DEPDIR)/mandelSSE-mandel.Po
-	-rm -f ./$(DEPDIR)/mandelSSE-sse.Po
-	-rm -f ./$(DEPDIR)/mandelSSE-xaos.Po
+	-rm -rf ./$(DEPDIR)
 	-rm -f Makefile
 maintainer-clean-am: distclean-am maintainer-clean-generic
 
@@ -620,18 +609,18 @@ uninstall-am:
 
 .MAKE: all install-am install-strip
 
-.PHONY: CTAGS GTAGS TAGS all all-am am--depfiles check check-am clean \
-	clean-generic clean-noinstPROGRAMS cscopelist-am ctags \
-	ctags-am distclean distclean-compile distclean-generic \
-	distclean-hdr distclean-tags distdir dvi dvi-am html html-am \
-	info info-am install install-am install-data install-data-am \
-	install-dvi install-dvi-am install-exec install-exec-am \
-	install-html install-html-am install-info install-info-am \
-	install-man install-pdf install-pdf-am install-ps \
-	install-ps-am install-strip installcheck installcheck-am \
-	installdirs maintainer-clean maintainer-clean-generic \
-	mostlyclean mostlyclean-compile mostlyclean-generic pdf pdf-am \
-	ps ps-am tags tags-am uninstall uninstall-am
+.PHONY: CTAGS GTAGS TAGS all all-am check check-am clean clean-generic \
+	clean-noinstPROGRAMS cscopelist-am ctags ctags-am distclean \
+	distclean-compile distclean-generic distclean-hdr \
+	distclean-tags distdir dvi dvi-am html html-am info info-am \
+	install install-am install-data install-data-am install-dvi \
+	install-dvi-am install-exec install-exec-am install-html \
+	install-html-am install-info install-info-am install-man \
+	install-pdf install-pdf-am install-ps install-ps-am \
+	install-strip installcheck installcheck-am installdirs \
+	maintainer-clean maintainer-clean-generic mostlyclean \
+	mostlyclean-compile mostlyclean-generic pdf pdf-am ps ps-am \
+	tags tags-am uninstall uninstall-am
 
 .PRECIOUS: Makefile
 
diff --git a/src/mandel.c b/src/mandel.c
index 4d399de..44726e9 100644
--- a/src/mandel.c
+++ b/src/mandel.c
@@ -8,6 +8,8 @@
 #define GLOBAL
 #include "common.h"
 
+#include "version.h"
+
 // XaoS algorithm implemenation
 #include "xaos.h"
 
@@ -58,7 +60,7 @@ int main(int argc, char *argv[])
     } else
         usage(argv);
 
-    printf("\n[-] Mandelbrot Zoomer by Thanassis.\n");
+    printf("\n[-] Mandelbrot Zoomer by Thanassis, version: %s\n", version);
     if (!bAutoPilot)
         puts("[-] Note you can launch with option '-a' to enable autopilot.");
 
diff --git a/src/version.h.in b/src/version.h.in
new file mode 100644
index 0000000..eada2e0
--- /dev/null
+++ b/src/version.h.in
@@ -0,0 +1 @@
+const char version[] = "2.1-@SCM_REVISION@";