How do I predict how the TCP wrapper would handle a specific request for service?

Guys,

Use tcpdmatch command. predict how tcpd would handle a sshd request from the local system:

tcpdmatch sshd localhost

The same request, pretending that hostname lookup failed:

tcpdmatch sshd 192.168.1.5

To predict what tcpd would do when the client name does not match the client address:

tcpdmatch sshd paranoid

Replace sshd with in.telnetd, or ftpd and so on. You can use all daemon names specified in inetd.conf or xinetd.conf file.

try :)