The default channels

In UnixWare, by default, sendmail is installed with a sendmail.cf file with three mail channels pre-configured:

• The local channel, which handles delivery of mail to local users.

• The SMTP channel, for Internet mail using name service to resolve hostnames and the Simple Mail Transfer Protocol.

• The badhost delay channel, to queue messages that temporarily fail address verification because of unavailability of a name server. (This is analogous to the MMDF name service delay channel in SCO OpenServer Release 5).