#include <sasl/sasl.h>
int sasl_checkapop(sasl_conn_t *conn, 
                      const char *challenge, 
                      unsigned challen, 
                      const char *response, 
                      unsigned resplen); 
 
sasl_checkapop() will check an APOP challenge/response. APOP is an optional POP3 (RFC 1939) authentication command which uses a shared secret (password). The password is stored in the SASL secrets database. For information on the SASL shared secrets database see the System Administrators Guide in the doc/ directory of the SASL distribution.
If called with a NULL challenge, sasl_checkapop() will check to see if the APOP mechanism is enabled.