dfindpm - find previous matching record using secondary index
rno_t dfindpm(buffer, fcb)
Dfindpm searches for duplicate secondary keys in reverse
secondary key order. Before calling dfindpm, call dseti(C-3) to
select the desired secondary index. Call dfindlm(C-3) to find the
last key value in the secondary index. Each subsequent call to
dfindpm returns the previous record in reverse secondary key
order whose keys match the record returned by dfindlm(C-3). If
dnumidx(C-3) has been called prior to this function, only the
first n fields of the current index are compared; otherwise, all
fields of the current index are compared. The beginning contents
of buffer are ignored by dfindpm.
Dfindpm maintains the current position in the secondary index, so
additional records may be fetched in reverse secondary key order
by calling the dfindpm function repeatedly.
Fcb is the file block pointer returned by dlopen(C-3) or
The returned record number may be saved and used on a subsequent
call to dread(C-3).
dlopen(C-3), dopen(C-3), dseti(C-3), dfindlm(C-3),
Chapter 4, RMS Programming Guide
Dfindpm returns a value of BAD (-1) if an I/O error occurred or
if there is no record that contains field values equal to the
last values returned. If no record is found, the contents of
buffer are undefined.