diff --git a/doc/efun/set_extra_wizinfo b/doc/efun/set_extra_wizinfo
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+++ b/doc/efun/set_extra_wizinfo
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+SYNOPSIS
+        void set_extra_wizinfo (object wiz, mixed extra)
+        void set_extra_wizinfo (string wiz, mixed extra)
+        void set_extra_wizinfo (int    wiz, mixed extra)
+
+DESCRIPTION
+        Set the value <extra> as the 'extra' information for the wizlist
+        entry of <wiz>.
+
+        If <wiz> is an object, the entry of its creator (uid) is used.
+        If <wiz> is a string (a creator aka uid), it names the entry
+        to use.
+        If <wiz> is the number 0, the data is set in the default wizlist
+        entry. It can be used to store data for the lifetime of this
+        driver run, like the time of the last reboot.
+
+        The <extra> argument may be any value.
+
+        The function causes a privilege violation.
+
+SEE ALSO
+        get_extra_wizinfo(E), set_extra_wizinfo_size(E), wizlist_info(E)