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NbrOfRecords
Get the number of active records in fixed-length data file.
Short Name
DATENT()
Type
Low-Level fixed-length data file function
Declaration
LONG NbrOfRecords(COUNT datno)
Description
NbrOfRecords() returns the number of active data records for the fixed length data file designated by datno.
Each time a new record is added to the file, the count of active records is incremented. Each time a record is deleted, the active count is decremented. A record is added by the Low-Level function NewData() or the ISAM function AddRecord(). A record is deleted by the Low-Level function ReleaseData() or the ISAM function DeleteRecord().
Note: A huge file may return values greater than 4 GB. This function returns the low-order 4-byte word of the 8-byte number of keys. To get the high-order 4-byte word, call ctGETHGH(). A return of zero is not necessarily an error if there are exactly a multiple 4 GB worth of key values.
Return
If an error occurs or if there are no active data records, NbrOfRecords() returns a value of zero. Otherwise, NbrOfRecords() returns the number of active fixed data records in the data file. After a call to NbrOfRecords() returns a zero, check the value of uerr_cod: if uerr_cod is non-zero, an error condition was detected; otherwise, no active records are in the file. See c-tree Error Codes in the c-tree Programmer’s Reference Guide for a complete listing of valid c-tree error values.
Example
COUNT datno;
scanf("%d",&datno);
printf("\nThere are %ld active records in file #%d.",
NbrOfRecords(datno),datno);
ee also
NewData(), AddRecord(), DeleteRecord(), ReleaseData()
