Date: Mon, 1 Aug 2005 22:04:25 +0300 From: victor cruceru <victor.cruceru@gmail.com> To: ticso@cicely.de Cc: Marc Olzheim <marcolz@stack.nl>, freebsd-hackers@freebsd.org Subject: Re: O_NONBLOCK for devices with removable media Message-ID: <494025505080112043f8a0554@mail.gmail.com> In-Reply-To: <20050801184731.GD26656@cicely12.cicely.de> References: <494025505080104427c3f91f6@mail.gmail.com> <20050801130502.GA39470@stack.nl> <494025505080106336a329bb@mail.gmail.com> <20050801173047.GC26656@cicely12.cicely.de> <4940255050801114161c1cea3@mail.gmail.com> <20050801184731.GD26656@cicely12.cicely.de>
next in thread | previous in thread | raw e-mail | index | archive | help
In conclusion:=20 any difference between open with O_NONBLOCK and open without it for this=20 kind of devices? Because man 2 open says: ---------------------------------------------------------------------------= ------------------------- If the O_NONBLOCK flag is specified and the open() system call would result= =20 in the process being blocked for some reason (e.g., waiting for carrier on a dialup line), open() returns immediately. The descriptor remains in non- blocking mode for subsequent operations. ---------------------------------------------------------------------------= ------------------------- Thanks victor cruceru On 8/1/05, Bernd Walter <ticso@cicely12.cicely.de> wrote: >=20 > On Mon, Aug 01, 2005 at 09:41:30PM +0300, victor cruceru wrote: > > Well, if you are doing this from a daemon (multiplexing a lot of events= ) > > which is blocked in this open syscall, even 1 second is not reasonable.= =20 > In > > my case it is something more than 30 of seconds (again, on a 5.4 box).= =20 > I'll > > give it a try on FreeBSD 6. I'm currently investigating if there is > > something like TEST_UNIT_READY (for both ATAPI and SCSI) which can be= =20 > issued > > on a control device (i.e. /dev/ata) >=20 > What do you expect it to do? > Ask the device about the state or always fail, because it is not > allowed to ask the device? > In your case you have a broken device, this isn't much of an argument. > A resonable reply time for a USB device would be less then 10ms. >=20 > -- > B.Walter BWCT http://www.bwct.de > bernd@bwct.de info@bwct.de >=20 >
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?494025505080112043f8a0554>