pam_fail_delay
specifies the minimum delay for the
PAM library to use when an authentication error occurs. The actual delay
can vary by as much at 25%. If this function is called multiple times,
the longest time specified by any of the call will be used.
The delay is invoked if an authentication error occurs during the
pam_authenticate
or pam_chauthtok
function calls.
Independent of the success of
pam_authenticate
or pam_chauthtok
,
the delay time is reset to its default value of 0 when the PAM library returns
control to the application from these two functions.