POSIX shm mmap question (newbie)

[Richard]

Linux SuSE 8.2, GNU C

I feel like a dope for asking this, but here goes: I've created a
POSIX shared memory segment and mmap()'ed it into two processes
(writer and reader). When I get to the end of the mapped file, I'd
like to rewind to the "top" of the file and start over. It's a
simple little thing, and I've been browsing web search hits and the
c.u.p. Google archives all day without much luck.

(1) This is readily possible to do, right?

(2) Reference, web link, or discussion?

Signed,
Sleepless In Seattle

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