[herrold@centos-5 ~]$ ssh emac
Password:
Last login: Thu Jan 24 20:55:06 2008 from couch.basement.
Welcome to Darwin!
emac:~ herrold$ mkdir temp
emac:~ herrold$ cd temp
emac:~/temp herrold$ vi acme
emac:~/temp herrold$ cat acme
red dead

emac:~/temp herrold$ sed -i -e 's/d d/d h/' acme
emac:~/temp herrold$ cat acme
red head

emac:~/temp herrold$ uname -a
Darwin emac.first.lan 8.11.0 Darwin Kernel Version 8.11.0: Wed Oct 10 18:26:00 PDT 2007; root:xnu-79