+sets
+.B "\-\-entire\-thread"
+The caller can disable this behaviour by setting
+.B \-\-entire\-thread=false
+.RE
+.RS 4
+.TP 4
+.B sexp
+
+The output is formatted as an S-Expression (sexp). This
+format is more robust than the text format for automated
+processing. The nested structure of multipart MIME messages is
+reflected in nested S-Expression output. By default,
+S-Expression output includes all messages in a matching thread;
+that is, by default,
+
+.B \-\-format=sexp
+sets
+.B "\-\-entire\-thread"
+The caller can disable this behaviour by setting
+.B \-\-entire\-thread=false