From owner-freebsd-questions@FreeBSD.ORG  Mon Sep 13 17:21:11 2004
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Date: Mon, 13 Sep 2004 12:21:10 -0500
From: Dan Nelson <dnelson@allantgroup.com>
To: Jesse Guardiani <jesse@wingnet.net>
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Subject: Re: mkfifo - disk backed?
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In the last episode (Sep 13), Jesse Guardiani said:
> Just curious: Are FIFOs made by mkfifo disk backed? Do they go away
> between reboots? Do they lose data between reboots?

Fifos are just pipes with a visible physical name.   The fifo itself
stays in the filesystem after a reboot, but since all the data passing
is handled in the kernel, a reboot will blow away any data (including
the processes reading/writing that data :).  If your FIFO is on an NFS
mount, a reboot of the remote server will have no effect on the
client's use of the fifo (since all fifo traffic is handled locally on
the client).

-- 
	Dan Nelson
	dnelson@allantgroup.com