Re: Exclusive access to block devices

Bernd Eckenfels (ukd1@rz.uni-karlsruhe.de)
4 May 1996 04:18:16 GMT

Grant R. Guenther <grant@gear.torque.net> wrote:
> There doesn't appear to be any general way to specify that an
> ioctl should only be executed if the access count is == 1, or to
> test that a block device is not mounted or otherwise open ... (While
> an absolute race-free lock would be nice, a simple busy test would be
> adequate for the application.)

You can use O_EXCL in conjunction with fstat(). The generic SCSI driver
seems to support that. Problem may be root access, not sure if it works, but
thats what the flag is for :)

Greetings
Bernd

-- 
  (OO)      -- Bernd_Eckenfels@Wittumstrasse13.76646Bruchsal.de --
 ( .. )  ecki@lina.{inka.de,ka.sub.org}  http://home.pages.de/~eckes/
  o--o     *plush*  2048/93600EFD  eckes@irc  +4972573817  *plush*
(O____O)       If privacy is outlawed only Outlaws have privacy