From owner-freebsd-hardware  Wed Apr 17  6:20: 5 2002
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From: "Nick Hibma" <n_hibma@van-laarhoven.org>
To: "Bruce Evans" <bde@zeta.org.au>,
	"Peter Haight" <peterh@sapros.com>
Cc: <hardware@FreeBSD.ORG>
References: <20020417003939.B8131-100000@gamplex.bde.org>
Subject: Re: Reading from the USB ugen device. 
Date: Wed, 17 Apr 2002 15:22:31 +0200
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> Here the problem may be the more immediate one that usb returns EIO
> instead of EWOULDBLOCK when it can't proceed.

EIO is only returned in case of error. I was mistaken. EWOULDBLOCK can never
be returned because the ugen driver can't know whether or no the transfer is
going to block. There is no such thing as a poll for data on the USB bus.

Nick


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