From: Eric W. Biederman > Sent: 30 May 2019 16:38 > ebied...@xmission.com (Eric W. Biederman) writes: > > > Which means I believe we have a semantically valid change in behavior > > that is causing a regression. > > I haven't made a survey of all of the functions yet but > fucntions return -ENORESTARTNOHAND will never return -EINTR and are > immune from this problem.
Eh? ERESTARTNOHAND just makes the system call restart if there is no signal handler, EINTR should still be returned if there is a handler. All the functions that have a temporary signal mask are likely to be expected to work the same way and thus have the same bugs. http://pubs.opengroup.org/onlinepubs/9699919799/functions/pselect.html# isn't overly helpful. But I think it should return EINTR even if there is no handler unless SA_RESTART is set: [EINTR] The function was interrupted while blocked waiting for any of the selected descriptors to become ready and before the timeout interval expired. If SA_RESTART has been set for the interrupting signal, it is implementation-defined whether the function restarts or returns with [EINTR]. David - Registered Address Lakeside, Bramley Road, Mount Farm, Milton Keynes, MK1 1PT, UK Registration No: 1397386 (Wales)
