The behavior of ORAC-DR is entirely controlled by the command line
options entered at startup. From that point on, the system either
takes its reduction recipe instructions from the file headers (this is
the default) or uses a hardwired recipe given on the command line
itself. The recipe is, in fact, the only allowed parameter on the
command line - all the rest are options. Once you start an instance of
oracdr up, there is no further control over it; this is a considerable
change from the situation with CGS4DR, for example, where the same
package remains up once you start it, and changes are made within the
package. Corollary: if the pipeline fails to find a required
calibration frame, for example, the only logical thing for it to do is
exit cleanly, telling you why it did so. There is no control from
within the pipeline. Note that once the full ORAC system is available,
there will be plenty of pre-checking that your calibration frames will
indeed exist and be appropriate. Until that point, the behavior of
the system is logical if you understand the underlying philosophy and
do not expect to be able to control the pipeline in real time.
ORAC-DR: Overview and General Introduction