This optional parameter specifies the name of the file where authentication log messages are to be written. You can use any of the special characters defined. For more information about special characters, see Section 3.3. Special formatters. The default value is %L/password.log. Special character %0 is replaced by the result of the authentication and %1 by the reason string.

If the Filename parameter starts with a vertical bar character (‘|’), the rest of the filename is assumed to be a program to which the output is to be piped. Otherwise the output is appended to the named file:

# Pipe to my-log-prog
Filename |/usr/local/bin/my-log-prog