Re: select() setting ERESTARTNOHAND (514).

[David Miller <davem@davemloft.net>]

From: Sean Reifschneider <jafo@tummy.com>
Date: Wed, 10 Jan 2007 16:42:38 -0700

> In looking at the select() code, I see that there are definitely cases
> where sys_select() or sys_pselect7() can return -ERESTARTNOHAND.  However,
> I don't know if this is expected to be caught elsewhere, or if returning it
> here would send it back to user-space.  Worse, I don't fully understand
> what the impact would be of trapping the ERESTARTNOHAND in the
> sys_select/sys_pselect7 functions would be.

It gets caught by the return into userspace code.

Specifically the signal dispatch should repair that return
value to a valid error return code when it tries to dispatch
the signal that select() set in the task struct.

Note that select() only returns these values when signal_pending()
is true.