man: document that using sd_journal APIs might cause dlopen to happen

diff --git a/man/sd-journal.xml b/man/sd-journal.xml
index d143cb4a0f7ecc36bd148ffff14bb784557d203c..5908f98e68a7c524efe34db8699843b9089f60c3 100644 (file)
--- a/man/sd-journal.xml
+++ b/man/sd-journal.xml
@@ -86,6 +86,17 @@
     — are fully thread-safe and may be called from multiple threads in parallel.</para>
   </refsect1>
 
+  <refsect1>
+    <title>Optional dependencies</title>
+
+    <para>Depending on which build-time options are enabled, functions that operate on
+    <structname>sd_journal</structname> objects might cause optional shared libraries to be dynamically
+    loaded via
+    <citerefentry project='man7'><refentrytitle>dlopen</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
+    such as decompression libraries (xz, lz4, zstd) or cryptographic libraries (gcrypt).
+    </para>
+  </refsect1>
+
   <xi:include href="libsystemd-pkgconfig.xml" />
 
   <refsect1>