BSD tty security, part 4: What You Can Look Forward To

[John F Haugh II]

In article <18954 at sdcc6.ucsd.edu> muller at sdcc10.ucsd.edu (Keith Muller) writes:
>In article <1991May2.202847.15537 at wpi.WPI.EDU>, entropy at wpi.WPI.EDU (Lawrence C Foard) writes:
>I would tend to want an open of /dev/tty to always check the current
>access to the controlling terminal.

The current implementations of /dev/tty don't cause the open to go
through the filesystem.  Nor would that always be possible - the
"current access" can be completely meaningless if there are more than
one (or even none) instances of that device.

One of the advantages of "POSIX-like" tty subsystems is that /dev/tty
operations can be restricted by "session id".  Dan can tell you what
is wrong with how POSIX works with regard to this feature ...
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