Date: Tue, 1 Oct 2002 16:12:08 +0000 From: "Weston M. Price" <wmprice@direcway.com> To: freebsd-questions@freebsd.org Subject: Re: Character Devices vs. Block Devices Message-ID: <200210011612.08538.wmprice@direcway.com> In-Reply-To: <200210011519.59430.wmprice@direcway.com> References: <200210011519.59430.wmprice@direcway.com>
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So, given this, I am assuming that hard drives are treated as raw devices= =20 exclusively? That is, no intermediate buffers are maintained between the = user=20 process and the device: =46rom The Design and Implementation of the 4.4 BSD operating system: "The character interface does not copy the user data into a kernel buffer= =20 before putting then on an I/O queue. Rather, it arranges to have the I/O = done=20 directly to or from the address space of the process. " Is this valid on FreeBSD?=20 Regard, Weston On Tuesday 01 October 2002 03:19 pm, Weston M. Price wrote: > Hello, > =09A quick ls of my dev directory revealed that each one of my hard dri= ves is > considered a character device by the system. Example: > > crw-r----- 2 root operator 116, 0x00010002 Aug 19 16:09 /dev/ad0 > crw-r----- 2 root operator 116, 0 Aug 19 16:09 /dev/ad0a > crw-r----- 2 root operator 116, 1 Aug 19 16:09 /dev/ad0b > crw-r----- 2 root operator 116, 2 Aug 19 16:09 /dev/ad0c > crw-r----- 2 root operator 116, 3 Aug 19 16:09 /dev/ad0d > crw-r----- 2 root operator 116, 4 Aug 19 16:09 /dev/ad0e > crw-r----- 2 root operator 116, 5 Aug 19 16:09 /dev/ad0f > crw-r----- 2 root operator 116, 6 Aug 19 16:09 /dev/ad0g > crw-r----- 2 root operator 116, 7 Aug 19 16:09 /dev/ad0h > > What I am confused about, aren't hard drives treated as block devices o= n > most systems? What am I missing? > > Regards, > > Weston > > > To Unsubscribe: send mail to majordomo@FreeBSD.org > with "unsubscribe freebsd-questions" in the body of the message To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-questions" in the body of the message
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