.TP
\fIISO 8601 point-in-time\fR
An ISO 8601 point-in-time specification, such as
.QW \fICCyymmdd\fBT\fIhhmmss\fR,
where \fBT\fR is the literal
.QW T ,
.QW "\fICCyymmdd hhmmss\fR" ,
.QW \fICCyymmdd\fBT\fIhh:mm:ss\fR ,
or
.QW \fICCyymmdd\fBT\fIhh:mm:ss\fR .
Note that only these three formats are accepted.
.QW \fICCyy-mm-dd\fBT\fIhh:mm:ss\fR.
Note that only these four formats are accepted.
The command does \fInot\fR accept the full range of point-in-time
specifications specified in ISO8601.  Other formats can be recognized by
giving an explicit \fB\-format\fR option to the \fBclock scan\fR command.
.TP
\fIrelative time\fR
A specification relative to the current time.  The format is \fBnumber
unit\fR. Acceptable units are \fByear\fR, \fBfortnight\fR,