Verification

Once (you think) you have spamd up and running, verify it to make sure. This is very simple to do. Simply take an email message (just one!) and feed it to spamc(1). For example, if the message is saved in ./test.mail, run
$ spamc < ./test.mail | grep '^X-Spam'
If spamassassin is up and running then you'll see some information like

X-Spam-Status: No, hits=3.7 required=6.0
X-Spam-Level: ***
X-Spam-Checker-Version: SpamAssassin 2.55 (1.174.2.19-2003-05-19-exp)

or

X-Spam-Status: Yes, hits=9.3 required=6.0
X-Spam-Level: *********
X-Spam-Checker-Version: SpamAssassin 2.55 (1.174.2.19-2003-05-19-exp)
X-Spam-Report:   ---- Start SpamAssassin results
X-Spam-Flag: YES

(for a little more fun, see Appendix A)