diff --git a/doc/master/runtime_warning b/doc/master/runtime_warning
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+SYNOPSIS
+        void runtime_warning( string msg, string curobj, string prog, int line
+                            , int inside_catch)
+
+DESCRIPTION
+        This function is called to let the mudlib handle a runtime warning,
+        e.g. by logging it into a database.
+
+        <msg> is the warning message.
+        <curobj> is the name of the current object which caused the message
+              (the object itself might already be destructed), or 0 if there
+              is none.
+        <prog>, <line> determine the name of the program and the line where
+              the error occured if the current object exists, otherwise
+              they are 0.
+        <inside_catch> : != 0 if the warning occurs inside a catch().
+
+        The driver is limited to three nested warnings, to prevent
+        an endless recursion in case runtime_warning() itself causes
+        warnings.
+
+HISTORY
+        Introduced in LDMud 3.3.551.
+        LDMud 3.3.705 added the <inside_catch> argument.
+
+SEE ALSO
+        runtime_error(M)