docs: Explain --seccomp data format

Well, at least point to the libseccomp api that generates it.

1 files changed, 5 insertions, 1 deletions

diff --git a/bwrap.xml b/bwrap.xml
index b183793..543a24a 100644
--- a/bwrap.xml
+++ b/bwrap.xml
@@ -192,7 +192,11 @@
   <variablelist>
     <varlistentry>
       <term><option>--seccomp <arg choice="plain">FD</arg></option></term>
-      <listitem><para>Load and use seccomp rules from <arg choice="plain">FD</arg></para></listitem>
+      <listitem><para>
+        Load and use seccomp rules from <arg choice="plain">FD</arg>.
+        The rules need to be in the form of a compiled eBPF program,
+        as generated by seccomp_export_bpf.
+      </para></listitem>
     </varlistentry>
   </variablelist>
 </refsect1>