diff --git a/ChangeLog b/ChangeLog
index df971f6..a456ecd 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,4 +1,28 @@
 lrzip ChangeLog
+NOVEMBER 2010, version 0.5 Con Kolivas
+* Changed offset encoding in rzip stage to use variable byte width offsets
+instead of 64 bits wide. Makes for better compression and slightly faster.
+* Write the byte width into the file before each block.
+* Shrunk match lengths to maximum of 16 bits again as per original rzip as the
+larger offsets did not achieve greater compression and made final size larger.
+* New file format not backwards compatible due to variable byte widths.
+* Rewrote memory initialisation to have a pre-allocation stage to try and
+find the maximum memory usable and defragment ram.
+* Use reduced window size if allocating memory fails at higher size.
+* Change use of malloc to mmap to make it possible to address up to 44 bit
+sized offsets even on 32 bit machines on decompression. Still unable to use
+greater than 2GB windows on 32 bit machines and unsure if this is fixable.
+* Reworked the STDIN code to use an anonymous mmap and read in stdin into this
+to make it possible to compress from STDIN without the need for temporary
+files. As the file size is not known in advance, memory allocation is set to
+large and byte width to equivalent size.
+* Reallocation of ram where possible to minimise risk of running out of memory
+in the middle of a compression phase, and flushing to disk to empty dirty ram
+for the same reason.
+* More robust fatal warnings.
+* Numerous cleanups and tidying of code and addition of comments.
+* Updated documentation to reflect changes.
+
 OCTOBER 2010, version 0.47, Con Kolivas
 * Fix the symlinking problem when DESTDIR is in use reported by a billion
 people.
diff --git a/README b/README
index cf45c0f..44dc9e9 100644
--- a/README
+++ b/README
@@ -1,4 +1,4 @@
-lrzip v0.50
+lrzip v0.5
 
 Long Range ZIP or Lzma RZIP
 
diff --git a/WHATS-NEW b/WHATS-NEW
index 1a6552b..5e704b0 100644
--- a/WHATS-NEW
+++ b/WHATS-NEW
@@ -7,7 +7,8 @@ Updated a lot of the stdin code.
 The most common scenario of compression from stdin now works without
 temporary files.
 Lots more meaningful warnings if failure occurs.
-Lots of code cleanups and tidying.
+May be able to decompress files on 32 bit machines that were compressed on 64
+bit machines with >2GB windows now if there is enough ram.
 
 lrzip-0.46
 
diff --git a/configure b/configure
index 593927e..9e27bc8 100755
--- a/configure
+++ b/configure
@@ -1,6 +1,6 @@
 #! /bin/sh
 # Guess values for system-dependent variables and create Makefiles.
-# Generated by GNU Autoconf 2.67 for lrzip 0.47.
+# Generated by GNU Autoconf 2.67 for lrzip 0.5.
 #
 # Report bugs to <kernel@kolivas.org>.
 #
@@ -551,9 +551,9 @@ MAKEFLAGS=
 
 # Identity of this package.
 PACKAGE_NAME='lrzip'
-PACKAGE_TARNAME='lrzip-0.47'
-PACKAGE_VERSION='0.47'
-PACKAGE_STRING='lrzip 0.47'
+PACKAGE_TARNAME='lrzip-0.5'
+PACKAGE_VERSION='0.5'
+PACKAGE_STRING='lrzip 0.5'
 PACKAGE_BUGREPORT='kernel@kolivas.org'
 PACKAGE_URL=''
 
@@ -1221,7 +1221,7 @@ 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 lrzip 0.47 to adapt to many kinds of systems.
+\`configure' configures lrzip 0.5 to adapt to many kinds of systems.
 
 Usage: $0 [OPTION]... [VAR=VALUE]...
 
@@ -1269,7 +1269,7 @@ Fine tuning of the installation directories:
   --infodir=DIR           info documentation [DATAROOTDIR/info]
   --localedir=DIR         locale-dependent data [DATAROOTDIR/locale]
   --mandir=DIR            man documentation [DATAROOTDIR/man]
-  --docdir=DIR            documentation root [DATAROOTDIR/doc/lrzip-0.47]
+  --docdir=DIR            documentation root [DATAROOTDIR/doc/lrzip-0.5]
   --htmldir=DIR           html documentation [DOCDIR]
   --dvidir=DIR            dvi documentation [DOCDIR]
   --pdfdir=DIR            pdf documentation [DOCDIR]
@@ -1286,7 +1286,7 @@ fi
 
 if test -n "$ac_init_help"; then
   case $ac_init_help in
-     short | recursive ) echo "Configuration of lrzip 0.47:";;
+     short | recursive ) echo "Configuration of lrzip 0.5:";;
    esac
   cat <<\_ACEOF
 
@@ -1375,7 +1375,7 @@ fi
 test -n "$ac_init_help" && exit $ac_status
 if $ac_init_version; then
   cat <<\_ACEOF
-lrzip configure 0.47
+lrzip configure 0.5
 generated by GNU Autoconf 2.67
 
 Copyright (C) 2010 Free Software Foundation, Inc.
@@ -2014,7 +2014,7 @@ 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 lrzip $as_me 0.47, which was
+It was created by lrzip $as_me 0.5, which was
 generated by GNU Autoconf 2.67.  Invocation command line was
 
   $ $0 $@
@@ -5324,7 +5324,7 @@ cat >>$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 lrzip $as_me 0.47, which was
+This file was extended by lrzip $as_me 0.5, which was
 generated by GNU Autoconf 2.67.  Invocation command line was
 
   CONFIG_FILES    = $CONFIG_FILES
@@ -5386,7 +5386,7 @@ _ACEOF
 cat >>$CONFIG_STATUS <<_ACEOF || ac_write_fail=1
 ac_cs_config="`$as_echo "$ac_configure_args" | sed 's/^ //; s/[\\""\`\$]/\\\\&/g'`"
 ac_cs_version="\\
-lrzip config.status 0.47
+lrzip config.status 0.5
 configured by $0, generated by GNU Autoconf 2.67,
   with options \\"\$ac_cs_config\\"
 
diff --git a/configure.ac b/configure.ac
index 715d32c..24fd771 100644
--- a/configure.ac
+++ b/configure.ac
@@ -1,5 +1,5 @@
 dnl Process this file with autoconf to produce a configure script.
-AC_INIT([lrzip],[0.47],[kernel@kolivas.org],[lrzip-0.47])
+AC_INIT([lrzip],[0.5],[kernel@kolivas.org],[lrzip-0.5])
 AC_CONFIG_HEADER(config.h)
 # see what our system is!
 AC_CANONICAL_HOST
diff --git a/main.c b/main.c
index a99c026..d285a92 100644
--- a/main.c
+++ b/main.c
@@ -136,7 +136,7 @@ static void preserve_perms(int fd_in, int fd_out)
 	fchown(fd_out, st.st_uid, st.st_gid);
 }
 
-/* Open a temporary outputfile for stdout compression */
+/* Open a temporary outputfile to emulate stdout */
 static int open_tmpoutfile(void)
 {
 	int fd_out;
@@ -563,9 +563,8 @@ int main(int argc, char *argv[])
 	control.suffix = ".lrz";
 	control.outdir = NULL;
 
-	if (strstr(argv[0], "lrunzip")) {
+	if (strstr(argv[0], "lrunzip"))
 		control.flags |= FLAG_DECOMPRESS;
-	}
 
 	control.compression_level = 7;
 	control.ramsize = get_ram() / 104858ull; /* hundreds of megabytes */