Re: EINTR error in SunOS

Doug Royer <Doug(at)Royer(dot)com> writes:

> From the Linux 'nfs' man page:
>
> intr If an NFS file operation has a major timeout and it is
> hard mounted, then allow signals to interupt the file
> operation and cause it to return EINTR to the calling
> program. The default is to not allow file operations to
> be interrupted.
>
> Solaris 'mount_nfs' man page
>
> intr | nointr
> Allow (do not allow) keyboard interrupts to kill
> a process that is hung while waiting for a
> response on a hard-mounted file system. The
> default is intr, which makes it possible for
> clients to interrupt applications that may be
> waiting for a remote mount.
>
> The Solaris and Linux defaults seem to be the opposite of each other.

Actually they're the same, though differently worded. "Major timeout"
means the server has not responded for N milliseconds, not that the
client has decided to time out the request. If 'hard' is set, the
client will keep trying indefinitely, though you can interrupt it if
you've specified 'intr'.

> So I think we are saying the same thing.
>
> You can get EINTR with hard+intr mounts.

Yes, *only* if the user specifically decides to send a signal, or if
it uses SIGALRM or whatever. I agree that if you expect 'intr' to be
used, your code needs to handle EINTR.

> I am not sure what you get with soft mounts on a timeout.

The Linux manpage implies you get EIO.

-Doug