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deleted file mode 100644
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deleted file mode 100644
index b1e0a5e..0000000
--- a/libHX-3.26.tar.xz
+++ /dev/null
@@ -1,3 +0,0 @@
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-oid sha256:67e2dd0b5b888ab8c02362d043ac2d4dd26eb5bb976064603b57b3e3a7adb209
-size 358136
diff --git a/libHX-4.0.1.tar.asc b/libHX-4.0.1.tar.asc
new file mode 100644
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+++ b/libHX-4.0.1.tar.asc
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diff --git a/libHX-4.0.1.tar.xz b/libHX-4.0.1.tar.xz
new file mode 100644
index 0000000..0563a2a
--- /dev/null
+++ b/libHX-4.0.1.tar.xz
@@ -0,0 +1,3 @@
+version https://git-lfs.github.com/spec/v1
+oid sha256:d93d8dad3281628e9d4b418792105c64b662dbf61fc3be18324386eab3aa99b8
+size 362584
diff --git a/libHX.changes b/libHX.changes
index 468af95..48d4dd1 100644
--- a/libHX.changes
+++ b/libHX.changes
@@ -1,3 +1,13 @@
+-------------------------------------------------------------------
+Sun Oct  3 00:28:41 UTC 2021 - Jan Engelhardt <jengelh@inai.de>
+
+- Update to release 4.0.1
+  * lib: add ``HX_slurp_fd``, ``HX_slurp_file``
+  * proc: add ``HXproc_switch_user``
+  * proc: add ``HXproc_top_fd``
+  * socket: add ``HX_socket_from_env``
+  * opt: add ``HXOPT_KEEP_ARGV`` flag
+
 -------------------------------------------------------------------
 Tue Aug  3 22:23:47 UTC 2021 - Jan Engelhardt <jengelh@inai.de>
 
diff --git a/libHX.spec b/libHX.spec
index e88aabd..a60e24f 100644
--- a/libHX.spec
+++ b/libHX.spec
@@ -18,7 +18,7 @@
 
 Name:           libHX
 %define lname   libHX32
-Version:        3.26
+Version:        4.0.1
 Release:        0
 Summary:        Collection of routines for C and C++ programming
 License:        LGPL-2.1-or-later
@@ -70,7 +70,7 @@ mkdir obj
 pushd obj/
 %define _configure ../configure
 %configure --includedir="%_includedir/%name" --docdir="%_docdir/%name"
-make %{?_smp_mflags}
+%make_build
 popd
 
 %install
@@ -82,7 +82,7 @@ rm -f "$b/%_docdir/%name"/Makefile*
 find "$b/%_libdir" -type f -name "*.la" -delete
 
 %check
-make -C obj check %{?_smp_mflags}
+%make_build -C obj check
 
 %post   -n %lname -p /sbin/ldconfig
 %postun -n %lname -p /sbin/ldconfig