Re: [bug-grep] [patch] getting '--devices=skip' to work

[Paul Eggert]

Tim Waugh <address@hidden> writes:

>   https://bugzilla.redhat.com/beta/show_bug.cgi?id=135942

Of the coreutils programs that use O_NONBLOCK:

   chown and touch don't do I/O.
   dd uses O_NONBLOCK only when the user asks for it explicitly.
   shred uses it only on /dev/random.
   stty uses it only on its argument, which is supposed to be a device.
     (There is a FIXME that this assumption should be checked, but there's more
      to be fixed here than O_NONBLOCK.)
   tail does nonblocking reads in some cases but doesn't use select() or poll().

None of these uses would run afoul of the bug that you mentioned, as
far as I can tell.

POSIX is pretty vague about what O_NONBLOCK does, except for pipes,
fifos, and sockets.  So if we limited ourselves to what POSIX
required, coreutils would require several changes.  I wouldn't bother
with this, though, unless there's a real problem.