diff --git a/Makefile.am b/Makefile.am
index 16a30da..24e4b01 100644
--- a/Makefile.am
+++ b/Makefile.am
@@ -1,4 +1,8 @@
-SUBDIRS = lzma/C src
+SUBDIRS =
+if ENABLE_7ZIP
+SUBDIRS += lzma/C
+endif
+SUBDIRS += src
 
 man1_MANS = man/ugrep-indexer.1
 
diff --git a/Makefile.in b/Makefile.in
index 4421f60..a1021e0 100644
--- a/Makefile.in
+++ b/Makefile.in
@@ -87,6 +87,7 @@ PRE_UNINSTALL = :
 POST_UNINSTALL = :
 build_triplet = @build@
 host_triplet = @host@
+@ENABLE_7ZIP_TRUE@am__append_1 = lzma/C
 subdir = .
 ACLOCAL_M4 = $(top_srcdir)/aclocal.m4
 am__aclocal_m4_deps = $(top_srcdir)/m4/ax_check_brotlilib.m4 \
@@ -193,7 +194,7 @@ am__define_uniq_tagged_files = \
   unique=`for i in $$list; do \
     if test -f "$$i"; then echo $$i; else echo $(srcdir)/$$i; fi; \
   done | $(am__uniquify_input)`
-DIST_SUBDIRS = $(SUBDIRS)
+DIST_SUBDIRS = lzma/C src
 am__DIST_COMMON = $(srcdir)/Makefile.in $(srcdir)/config.h.in \
 	README.md ar-lib compile config.guess config.sub depcomp \
 	install-sh missing
@@ -350,7 +351,7 @@ target_alias = @target_alias@
 top_build_prefix = @top_build_prefix@
 top_builddir = @top_builddir@
 top_srcdir = @top_srcdir@
-SUBDIRS = lzma/C src
+SUBDIRS = $(am__append_1) src
 man1_MANS = man/ugrep-indexer.1
 EXTRA_DIST = README.md LICENSE.txt CONTRIBUTING.md CODE_OF_CONDUCT.md
 all: config.h
diff --git a/bin/win32/ugrep-indexer.exe b/bin/win32/ugrep-indexer.exe
index 64f2950..c091a86 100755
Binary files a/bin/win32/ugrep-indexer.exe and b/bin/win32/ugrep-indexer.exe differ
diff --git a/bin/win64/ugrep-indexer.exe b/bin/win64/ugrep-indexer.exe
index 1083390..cf3c187 100755
Binary files a/bin/win64/ugrep-indexer.exe and b/bin/win64/ugrep-indexer.exe differ
diff --git a/configure b/configure
index e5940fc..3a6267a 100755
--- a/configure
+++ b/configure
@@ -653,6 +653,8 @@ LIBOBJS
 PTHREAD_LIBS
 PTHREAD_CFLAGS
 EXTRA_CFLAGS
+ENABLE_7ZIP_FALSE
+ENABLE_7ZIP_TRUE
 PLATFORM
 host_os
 host_vendor
@@ -7808,6 +7810,14 @@ printf "%s\n" "yes" >&6; }
 fi
 
 fi
+ if test "x$with_7zip" = "xyes"; then
+  ENABLE_7ZIP_TRUE=
+  ENABLE_7ZIP_FALSE='#'
+else
+  ENABLE_7ZIP_TRUE='#'
+  ENABLE_7ZIP_FALSE=
+fi
+
 
 
 PTHREAD_CFLAGS=""
@@ -7959,6 +7969,10 @@ if test -z "${am__fastdepCC_TRUE}" && test -z "${am__fastdepCC_FALSE}"; then
   as_fn_error $? "conditional \"am__fastdepCC\" was never defined.
 Usually this means the macro was only invoked conditionally." "$LINENO" 5
 fi
+if test -z "${ENABLE_7ZIP_TRUE}" && test -z "${ENABLE_7ZIP_FALSE}"; then
+  as_fn_error $? "conditional \"ENABLE_7ZIP\" was never defined.
+Usually this means the macro was only invoked conditionally." "$LINENO" 5
+fi
 
 : "${CONFIG_STATUS=./config.status}"
 ac_write_fail=0
diff --git a/configure.ac b/configure.ac
index c1b6457..b133c9c 100644
--- a/configure.ac
+++ b/configure.ac
@@ -76,6 +76,7 @@ else
 fi
 
 fi
+AM_CONDITIONAL([ENABLE_7ZIP],[test "x$with_7zip" = "xyes"])
 
 AC_SUBST(EXTRA_CFLAGS)
 AC_SUBST([PTHREAD_CFLAGS], [""])
diff --git a/lzma/7zls.c b/lzma/7zls.c
index 34639db..bb28b00 100644
--- a/lzma/7zls.c
+++ b/lzma/7zls.c
@@ -34,6 +34,11 @@
 @copyright (c) BSD-3 License - see LICENSE.txt
 */
 
+/* to build and run 7zls:
+   cc -o 7zls 7zls.c C/libviiz.a
+   ./7zls ../tests/archive.7z
+*/
+
 #include <stdlib.h>
 #include <stdio.h>
 #include <string.h>
diff --git a/lzma/C/7zCrc.c b/lzma/C/7zCrc.c
index c995a8b..bcd318c 100644
--- a/lzma/C/7zCrc.c
+++ b/lzma/C/7zCrc.c
@@ -84,8 +84,9 @@ UInt32 Z7_FASTCALL CrcUpdateT1(UInt32 v, const void *data, size_t size, const UI
     #endif
     #endif
     #endif
-  #elif (defined(__clang__) && (__clang_major__ >= 3)) \
-     || (defined(__GNUC__) && (__GNUC__ > 4))
+  #elif ( (defined(__clang__) && (__clang_major__ >= 3)) ||	 \
+          (defined(__GNUC__)  && (__GNUC__ > 4)        )    ) && \
+        (__ARM_ARCH >= 8)
       #if !defined(__ARM_FEATURE_CRC32)
         #define __ARM_FEATURE_CRC32 1
         #if defined(__clang__)
diff --git a/lzma/C/Makefile.in b/lzma/C/Makefile.in
index 3abdfba..3f3d47c 100644
--- a/lzma/C/Makefile.in
+++ b/lzma/C/Makefile.in
@@ -90,13 +90,11 @@ build_triplet = @build@
 host_triplet = @host@
 subdir = lzma/C
 ACLOCAL_M4 = $(top_srcdir)/aclocal.m4
-am__aclocal_m4_deps = $(top_srcdir)/m4/ax_boost_regex.m4 \
-	$(top_srcdir)/m4/ax_check_brotlilib.m4 \
+am__aclocal_m4_deps = $(top_srcdir)/m4/ax_check_brotlilib.m4 \
 	$(top_srcdir)/m4/ax_check_bz2lib.m4 \
 	$(top_srcdir)/m4/ax_check_bzip3lib.m4 \
 	$(top_srcdir)/m4/ax_check_lz4lib.m4 \
 	$(top_srcdir)/m4/ax_check_lzmalib.m4 \
-	$(top_srcdir)/m4/ax_check_pcre2.m4 \
 	$(top_srcdir)/m4/ax_check_zlib.m4 \
 	$(top_srcdir)/m4/ax_check_zstdlib.m4 \
 	$(top_srcdir)/m4/ax_cxx_compile_stdcxx.m4 \
@@ -212,9 +210,6 @@ AUTOCONF = @AUTOCONF@
 AUTOHEADER = @AUTOHEADER@
 AUTOMAKE = @AUTOMAKE@
 AWK = @AWK@
-BASH_COMPLETION_CFLAGS = @BASH_COMPLETION_CFLAGS@
-BASH_COMPLETION_DIR = @BASH_COMPLETION_DIR@
-BASH_COMPLETION_LIBS = @BASH_COMPLETION_LIBS@
 CC = @CC@
 CCDEPMODE = @CCDEPMODE@
 CFLAGS = @CFLAGS@
@@ -222,7 +217,6 @@ CPPFLAGS = @CPPFLAGS@
 CSCOPE = @CSCOPE@
 CTAGS = @CTAGS@
 CXX = @CXX@
-CXXCPP = @CXXCPP@
 CXXDEPMODE = @CXXDEPMODE@
 CXXFLAGS = @CXXFLAGS@
 CYGPATH_W = @CYGPATH_W@
@@ -234,10 +228,6 @@ ECHO_T = @ECHO_T@
 ETAGS = @ETAGS@
 EXEEXT = @EXEEXT@
 EXTRA_CFLAGS = @EXTRA_CFLAGS@
-FISH_COMPLETION_CFLAGS = @FISH_COMPLETION_CFLAGS@
-FISH_COMPLETION_DIR = @FISH_COMPLETION_DIR@
-FISH_COMPLETION_LIBS = @FISH_COMPLETION_LIBS@
-GREP_PATH = @GREP_PATH@
 HAVE_CXX11 = @HAVE_CXX11@
 INSTALL = @INSTALL@
 INSTALL_DATA = @INSTALL_DATA@
@@ -260,22 +250,14 @@ PACKAGE_TARNAME = @PACKAGE_TARNAME@
 PACKAGE_URL = @PACKAGE_URL@
 PACKAGE_VERSION = @PACKAGE_VERSION@
 PATH_SEPARATOR = @PATH_SEPARATOR@
-PKG_CONFIG = @PKG_CONFIG@
-PKG_CONFIG_LIBDIR = @PKG_CONFIG_LIBDIR@
-PKG_CONFIG_PATH = @PKG_CONFIG_PATH@
 PLATFORM = @PLATFORM@
 PTHREAD_CFLAGS = @PTHREAD_CFLAGS@
 PTHREAD_LIBS = @PTHREAD_LIBS@
 RANLIB = @RANLIB@
-SED = @SED@
 SET_MAKE = @SET_MAKE@
 SHELL = @SHELL@
-SIMD_AVX2_FLAGS = @SIMD_AVX2_FLAGS@
-SIMD_AVX512BW_FLAGS = @SIMD_AVX512BW_FLAGS@
-SIMD_FLAGS = @SIMD_FLAGS@
 STRIP = @STRIP@
 VERSION = @VERSION@
-ZSH_COMPLETION_DIR = @ZSH_COMPLETION_DIR@
 abs_builddir = @abs_builddir@
 abs_srcdir = @abs_srcdir@
 abs_top_builddir = @abs_top_builddir@
diff --git a/lzma/C/README.txt b/lzma/C/README.txt
index 63b57c6..9c772dd 100644
--- a/lzma/C/README.txt
+++ b/lzma/C/README.txt
@@ -6,6 +6,9 @@ LZMA SDK is placed in the public domain.
 
 LZMA SDK by Igor Pavlov.
 
+Updated to apply YOKOTA Hiroshi's patches:
+https://salsa.debian.org/debian/7zip/-/blob/master/debian/patches/0002-Disable-hardware-acceleration-support-on-armel.patch?ref_type=heads
+
 Included in this directory is a new C API to simplify decompression:
 
 - viizip.h   declarations, see below (hides implementation details)
diff --git a/lzma/C/viizip.c b/lzma/C/viizip.c
index d6d7bef..ead1dbf 100644
--- a/lzma/C/viizip.c
+++ b/lzma/C/viizip.c
@@ -333,10 +333,11 @@ int viiget(struct viizip *viizip, char *name, size_t max, time_t *mtime, uint64_
   return res == SZ_OK ? 0 : -1;
 }
 
-/* decompress up to len bytes into buf[], return number of bytes decompressed */
+/* decompress up to len bytes into buf[], return number of bytes decompressed or -1 on error */
 ssize_t viidec(struct viizip *viizip, unsigned char *buf, size_t len)
 {
-  if (viizip == NULL)
+  /* if not initialized or not called viiget() then return error */
+  if (viizip == NULL || viizip->index == 0)
     return -1;
 
   switch (viizip->state)
diff --git a/man/ugrep-indexer.1 b/man/ugrep-indexer.1
index bffd374..cc426fd 100644
--- a/man/ugrep-indexer.1
+++ b/man/ugrep-indexer.1
@@ -1,4 +1,4 @@
-.TH UGREP-INDEXER "1" "December 31, 2023" "ugrep-indexer 0.9.5" "User Commands"
+.TH UGREP-INDEXER "1" "February 29, 2024" "ugrep-indexer 0.9.6" "User Commands"
 .SH NAME
 \fBugrep-indexer\fR -- file indexer to accelerate recursive searching
 .SH SYNOPSIS
@@ -33,7 +33,7 @@ Specifies indexing accuracy.  A low accuracy reduces the indexing
 storage overhead at the cost of a higher rate of false positive
 pattern matches (more noise).  A high accuracy reduces the rate of
 false positive regex pattern matches (less noise) at the cost of an
-increased indexing storage overhead.  An accuracy between 3 and 7
+increased indexing storage overhead.  An accuracy between 2 and 7
 is recommended.  The default accuracy is 5.
 .TP
 \fB\-.\fR, \fB\-\-hidden\fR
diff --git a/src/ugrep-indexer.cpp b/src/ugrep-indexer.cpp
index 756f802..876f3b0 100644
--- a/src/ugrep-indexer.cpp
+++ b/src/ugrep-indexer.cpp
@@ -34,7 +34,7 @@
 @copyright (c) BSD-3 License - see LICENSE.txt
 */
 
-#define UGREP_INDEXER_VERSION "0.9.5 beta"
+#define UGREP_INDEXER_VERSION "0.9.6"
 
 // use a task-parallel thread to decompress the stream into a pipe to search, also handles nested archives
 #define WITH_DECOMPRESSION_THREAD
@@ -350,6 +350,10 @@ struct Stream {
 
   void close()
   {
+    // close input separately when not associated with the file
+    if (input.file() != file && input.file() != NULL)
+      fclose(input.file());
+    // close the file
     if (file != NULL)
       fclose(file);
     file = NULL;
@@ -367,6 +371,14 @@ struct Stream {
 
     if (flag_decompress)
     {
+      // close the underlying pipe previously created with pipe() and fdopen()
+      if (input.file() != NULL)
+      {
+        // close and unassign input
+        fclose(input.file());
+        input.clear();
+      }
+
       partname.clear();
 
       // start decompression thread if not running, get pipe with decompressed input
@@ -378,7 +390,7 @@ struct Stream {
       }
 
       // read archive/compressed/plain data from the decompression thread chain pipe
-      input = reflex::Input(pipe_in);
+      input = pipe_in;
     }
     else
     {
@@ -434,10 +446,10 @@ struct Stream {
     // -z: open next archived file if any or close the compressed file/archive
     if (flag_decompress)
     {
-      // close the input FILE* and its underlying pipe previously created with pipe() and fdopen()
+      // close the pipe previously created with pipe() and fdopen()
       if (input.file() != NULL)
       {
-        // close and unassign input, i.e. input.file() == NULL, also closes pipe_fd[0] per fdopen()
+        // close and unassign input
         fclose(input.file());
         input.clear();
       }
@@ -449,7 +461,7 @@ struct Stream {
       if (pipe_in != NULL)
       {
         // assign the next extracted file as input to search
-        input = reflex::Input(pipe_in);
+        input = pipe_in;
 
         // start searching the next file in the archive
         return true;
diff --git a/src/zstream.hpp b/src/zstream.hpp
index 6439a6c..a0dd262 100644
--- a/src/zstream.hpp
+++ b/src/zstream.hpp
@@ -44,6 +44,7 @@
 #include <ctime>
 #include <climits>
 #include <exception>
+#include <stdexcept>
 #include <streambuf>
 #include <zlib.h>
 
@@ -538,8 +539,8 @@ class zstreambuf : public std::streambuf {
     // read and decompress zip file data into buf[0..len-1], return number of bytes decompressed, 0 for EOF or -1 for error
     std::streamsize decompress(unsigned char *buf, size_t len)
     {
-      // if no more data to decompress, then return 0 to indicate EOF
-      if (zend_)
+      // if header() was not called or no more data to decompress, then return 0 to indicate EOF
+      if (znew_ || zend_)
         return 0;
 
       std::streamsize num = 0;
@@ -1362,8 +1363,8 @@ class zstreambuf : public std::streambuf {
 
       catch (const std::invalid_argument&)
       {
-        /* non-seekable 7zip files cannot be decompressed,  */
-        cannot_decompress("non-seekable 7zip archive", pathname);
+        /* non-seekable and password-protected 7zip files cannot be decompressed */
+        cannot_decompress("7zip archive: encrypted data or 7z input is not seekable", pathname);
         file_ = NULL;
       }