[sclug] Postfix in words of one syllable

[John Bray]

I have a machine on ADSL which I consider locally to be vicarage.jrbray.org.uk, 
ie its hostname is vicarage, and the resolv.conf has the line 'search 
jrbray.org.uk', so a ping of 'vicarage.jrbray.org.uk' checks the local
IP address. I have registered the jrbray.org.uk domain, but the rest of the world has
never heard of the vicarage machine.

I want to set up postfix so any messages done with 'sendmail jrbray' go 
straight back into /var/spool/mail/jrbray, and any messages done with 
'sendmail jrbray at cix.co.uk' or whatever go off to smtp.dsl.pipex.com

I've tried fiddling with the relayhost, transport_maps, myorigin, 
mydomain and myhostname variables in /etc/postfix/main.cf but all to no 
avail.

Can someone explain very simply what options I should have, as the FAQs 
baffle me, and I can't find a tutorial.

John