# GETNONCE() (not included in filePro Lite)

After a call to ENCRYPT(), you can call GETNONCE() to get the "nonce" that was used.

#### Syntax

xx = GETNONCE()

"nonce" is the encryption mode used by filePro.

If "nonce" is not specified, filePro generates one.

Many consider it important to use a unique nonce with each piece of data encrypted. It does not reduce the cryptographic security (make the decryption any easier) of the encrypted data if the nonce is known unless the same nonce is reused with different data. An example of this might be encryption of data in medical records. You might use a nonce built from the patient ID and social security number. Then, a unique nonce could be generated (and regenerated) in processing from data which would not change stored in the record. If some of the nonce data might possibly change it wouldn't be to hard to build a routine to retrieve the encrypted field, decrypt it with the old data, re-encrypt it with the new data, and store it.