Reading MS signal metadata in rdheader

In general, it's useful to be able to read record metadata without reading the signals.

For multi-segment records, however, rdheader just reads the MS header by default (rd_segments=False), which means it doesn't read any of the signal metadata (e.g. signal names and units).

With rd_segments=True, rdheader reads the signal metadata and also all of the segment headers, which are not always needed.

For some applications it would be useful to have a middle ground of reading the multisegment header and the layout header, but not any of the segment headers. (Note that this is what isigopen does.)

I think this might make sense as the default behavior, since reading the signal metadata is a very common use of rdheader.

Beginnen Sie damit, die Einstiegspunkte rdheader und isigopen zu finden, und prüfen Sie, wie deren multisegment-, Layout- und Segment-Header gelesen werden. Sehen Sie sich vorhandene Tests für multisegment-Datensätze an und definieren Sie anschließend den Abschluss so, dass Signalmetadaten und der Layout-Header gelesen werden, ohne einzelne Segment-Header zu lesen, mit Abdeckung für den ausgewählten Standardwert oder die Option.