diff --git a/doc/efun/export_uid b/doc/efun/export_uid
new file mode 100644
index 0000000..5b1f6a3
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+++ b/doc/efun/export_uid
@@ -0,0 +1,15 @@
+SYNOPSIS
+        void export_uid(object ob)
+
+DESCRIPTION
+        Set the uid of object ob to the current object's effective uid.
+        It is only possible when object ob has an effective uid of 0.
+
+        This efun is not available in Morgengrauen.
+
+HISTORY
+        Since 3.2.1@47, this efun is availabe only when using euids.
+        Since 3.2.7, this efun is always available.
+
+SEE ALSO
+        seteuid(E), getuid(E), geteuid(E), uids(C), native(C)