dfind - find first active record in RMSfile
rno_t dfind (buffer, fcb)
Dfind finds the first active record in an opened RMSfile.
Fcb is the file block pointer returned by dlopen(C-3) or
The record number returned may be saved and used on a subsequent
call to dread(C-3). The record found is returned in buffer.
dlopen(C-3), dopen(C-3), dfindn(C-3), dread(C-3)
Chapter 4, RMS Programming Guide
Dfind returns a value of BAD (-1) if there is no active record or
if an I/O error occurred. If no record is found, the contents of
buffer are undefined.