A multi-segment record consists of two or more concatenated segments.
Each segment is an ordinary DB record, with its own header file and
signal file(s). In any given multi-segment record, all signals must
appear in the same order within each segment (signals may not be
omitted), and the sampling frequency of any given signal must be the
same in each segment. Segments of multi-segment records must be
ordinary records (it is not permitted to nest one multi-segment record
within another, for example), and the length of each segment must be
specified (the DB library does not impose this requirement on ordinary
records that are not part of a multi-segment record). There are no
other restrictions on segments; specifically, it is permitted to mix
segments with different storage formats, and for any segment to appear
more than once. A special header file (created either manually or by
using setmsheader) specifies the record name for each segment in
a multi-segment record. Once this special header exists, the
multi-segment record can be read by any DB application. Note that only
the signal files of the segments are "linked" by the multi-segment
record's header; annotation files associated with the individual
segments are not readable as part of the multi-segment record
(although an annotation file associated directly with the multi-segment
record can be created and read just as for an ordinary record). From
the point of view of a DB application, reading a multi-segment record is
exactly like reading an ordinary record; specifically,
isigsettime works as expected, permitting jumps forward and
backward between as well as within segments. Version 9.1 of the DB
library is the first to support reading and writing multi-segment
records.
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