+.B rescan \fR[\fBwait\fR] \fR[\fBfresh\fR]
+Rescan all roots for new or obsolete tracks.
+Requires the \fBrescan\fR right.
+.IP
+If the \fBwait\fR flag is present then the response is delayed until the rescan
+completes.
+Otherwise the response arrives immediately.
+This is primarily intended for testing.
+.IP
+If the \fBfresh\fR flag is present a rescan is already underway then a second
+rescan will be started when it completes.
+The default behavior is to piggyback on the existing rescan.
+.IP
+NB that \fBfresh\fR is currently disabled in the server source, so using this
+flag will just provoke an error.