There turns out not to be a single right answer.  Here are several small essays on the question:
----
======
    package require Expect

    log_user 0

    spawn ssh $account@phaseit.net
    expect {assword: }
    send $password\r
    expect $prompt
    send "grep $pattern $filename\r"
    expect -re "\[^\n]*\n(.*)\n.*$prompt"
    puts $expect_out(1,string)
    send exit\r
    expect eof
======

----
[[Show how to put it in a proc.]]



----
[[Show an RE-free version.]]


----
[[Show a more max_match-resistant version.]]


----
[[Introduce exception-handling.]]




----
[[Illustrate reliance on "[How to access the result of a remote command in Expect]"]]

----

[NEM] offers:
======
proc remote {user host command args} {
    exec ssh $user@$host $command {*}$args
}
remote $me $myhost grep foo /etc/passwd
======

Will the original requestor be able to say
======
set result [remote $me $myhost grep foo /etc/passwd]
======
and have the result of the command in $result?

I tried the example, but the ssh on my machine is somehow incompatible with the ssh on my $myhost. I know the error I received wasn't in $result though.



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