[ale] another scripting question

[Ben Phillips]

If I want sed to delete everything on every line of a file AFTER the first
word on the line, how would I do that?  Given sed's similarity to vi, it
seems like this shouldn't be hard.  Say I'm stripping a passwd file down to
just the usernames, so every line is like:

joe:x:100:100:group:blahblahblah
dave:x:100:100:group:blahblahblah
bob:x:100:100:group:blahblahblah

and I want:

joe
dave
bob


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Ben Phillips         /  '_' )         ,,,    then what is the opposite of
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