[lkml]   [1998]   [Jun]   [8]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
Messages in this thread
SubjectRe: >256 ptys (previous subject line was garbage)
In article <>,
Richard Gooch <Richard.Gooch@atnf.CSIRO.AU> wrote:
> writes:
>> Date: Fri, 5 Jun 1998 12:59:59 +0200 (MET DST)
>> From: Peter Svensson <>
>> I am not familiar with the reasons for using major/minor-pair for
>> locking so I don't know if another solution is feasable. Do you have
>> any pointers for additional reading? :-)
>> The problem is things like /dev/modem being a symlink (or perhaps even a
>> hard link) to /dev/ttyS0. So it would be useful to use a lockfile that
>> includes the major and minor device number, in addition to using a
>> lockfile that is based on the device name. The basic idea is that
>> people want to have different device names to refer to the same device,
>> so we need to lock based the major/minor devices.
>Well, I've seen one comment already questioning whether major/minor
>device locks are the better way of doing it, instead of flock(2).
>However, ignoring that, I think it would be simple enough to implement
>a non tty-specific locking scheme in devfs. I already have the auto
>ownership facility.
>What does this device locking need? Just limit the number of open(2)s
>to 1?

More than that.

You need a locking scheme that will support a getty listening on the
port (one open) and will also support things that want to grab the
port for outgoing traffic (the second open.)

david parsons \bi/ I [heart] mgetty

To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to

 \ /
  Last update: 2005-03-22 13:43    [W:0.039 / U:0.024 seconds]
©2003-2018 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site