List users in sasldb
sasldblistusers2 [-ffile] [-v]
sasldblistusers2 is used to list the users in the SASL password database (usually /etc/sasldb2). This will NOT list all the users in /etc/passwd, shadow, PAM, etc. only those created by SASL (via saslpasswd2).
-f file
use file for sasldb
-v
Print libsasl2 version number and exit.
rfc4422 - Simple Authentication and Security Layer (SASL)