/dev/ttyxx permissions

[Doug Gwyn]

In article <25090 at adm.brl.mil> sct60a.sunyct.edu!buck at sct60a.sunyct.edu (Jesse R. Buckley Jr.) writes:
>        Does anybody know is the permissions on a tty have any importance
>(besides the read and write ones of course)?

Some systems use the x bits to indicate whether or not "breakthrough writes"
(e.g. "wall", "write", "talk") are permitted on that tty.