+
+The `virusfree` [[PageSpec|ikiwiki/pagespec/attachment]] requires that
+ikiwiki be configured with a virus scanner program via the `virus_checker`
+option in the setup file. If using `clamav`, with `clamd`, set it to
+"clamdscan -". Or to use clamav without the `clamd` daemon, you
+could set it to "clamscan -".