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The header packet is automatically read and parsed when
bpipe_input
opens up the input data stream. A header field is
accessed by its name and its index. An index of ‘0’ will retrieve
the first field with a given name; an index of ‘BPHdrfIdx_LAST’ will
retrieve the last field. The number of fields with a given name is
returned by bpipe_hdrf_n
. If the program needs to go through the
list of header fields sequentially, repeated calls to
bpipe_hdrf_next
will step through the the header data fields
in the order that they appear in the header. Fields added by the
application before an input data stream is attached to the BPipe
will appear first in the list; those added after the header is read
will appear last.
See bpipe_hdrf_n and bpipe_hdrf_next.