Hallo,
  default installation of fcheck contains following option in config file
----
# Used for individual file checking (I.E. Possibly FCheck databases!)
#
File   = /var/lib/fcheck/fcheck.dbf
----
It doesn't seem to work as expected. I have to say, that I add /var/ directory
to checked areas (as suggesed by default config file) with some exclusions.

Doing it, I receive every 2 hours following report:
----
<not related part>
PROGRESS: validating integrity of Files
STATUS:
    WARNING: [lanmgr] /var/lib/fcheck/fcheck.dbf
	[Sizes: 212 - 2308939, Times: Feb 03 11:48 2010 - Feb 03 12:01 2010, CRCs: 2f75641c0bc94d02b5512070098510e8 - cc1966c14ddfc85360772ab71f78fd5e]

	PROGRESS: validating integrity of /
	STATUS:passed...

<not related part>

PROGRESS: validating integrity of /var/
STATUS:
    WARNING: [lanmgr] /var/lib/fcheck/fcheck.dbf
	[Sizes: 2175107 - 2308939, Times: Feb 03 12:00 2010 - Feb 03 12:01 2010, CRCs: 3fcd8b860336b8b929df88a8519172d3 - cc1966c14ddfc85360772ab71f78fd5e]
----

Look please to size: Database reports that size of fcheck.dbf is 212 byte.
It is right just in time, when database is checked. It corresponds to length
of header of this database before files are being recorded to this file.
This length is of course changed immediatelly when this check is finished.
During 2nd check you can see different length is reported, file is filled with
some new records.
Well, file is completed and report is sent to email ... and then, according to
cron record, new database is created ... with length of fcheck.dbf = 212 bytes
and so on.

I've found a hack how to stop it, but it is really hack, not solution. I create
a copy of fcheck.dbf named fcheck.old before creating new database and I point
check to this old file instead of live database file:
----
# Used for individual file checking (I.E. Possibly FCheck databases!)
#
#File   = /var/lib/fcheck/fcheck.dbf
File    = /var/lib/fcheck/fcheck.old
----
Additionally I have to change /etc/cron.d/fcheck - add command "cp -a ...." before
new database is created. You can see, my hack contains hard-coded filename
so it is not solution, I hope you can find better one.
----
30 */2  * * *   root    test -x /usr/sbin/fcheck && if ! /usr/sbin/fcheck -asxrf /etc/fcheck/fcheck.cfg >/var/run/fcheck.out 2>&1; then mailx -s "ALERT: [fcheck] `hostname --fqdn`" root </var/run/fcheck.out ; cp -a /var/lib/fcheck/fcheck.dbf /var/lib/fcheck/fcheck.old; /usr/sbin/fcheck -cadsxlf /etc/fcheck/fcheck.cfg ; fi ; rm -f /var/run/fcheck.out


Thank you for your help,
Pavel