Re: [PATCH RFC v2 0/7] epoll: Introduce new syscalls, epoll_ctl_batch and epoll_pwait1

[Fam Zheng <famz@redhat.com>]

On Wed, 02/04 13:38, Andy Lutomirski wrote:
> On Wed, Feb 4, 2015 at 2:36 AM, Fam Zheng <famz@redhat.com> wrote:
> > 2) epoll_pwait1
> > ---------------
> >
> > NAME
> >        epoll_pwait1 - wait for an I/O event on an epoll file descriptor
> >
> > SYNOPSIS
> >
> >        #include <sys/epoll.h>
> >
> >        int epoll_pwait1(int epfd, int flags,
> >                         struct epoll_event *events,
> >                         int maxevents,
> >                         struct timespec *timeout,
> >                         struct sigargs *sig);
> >
> > DESCRIPTION
> >
> >        The epoll_pwait1 system call differs from epoll_pwait only in parameter
> >        types. The first difference is timeout, a pointer to timespec structure
> >        which allows nanosecond presicion; the second difference, which should
> >        probably be wrapper by glibc and only expose a sigset_t pointer as in
> >        pselect6.
> >
> >        If timeout is NULL, it's treated as if 0 is specified in epoll_pwait
> >        (return immediately). Otherwise it's converted to nanosecond scalar,
> >        again, with the same convention as epoll_pwait's timeout.
> 
> Is the timeout absolute or relative?

Relative. Will document it. We can add a first flag for absolute timeout later.

Thanks.

Fam
> 
> I'd kind of like the ability to set timeouts on multiple clocks at the
> same time, but I can live without that.

Please see my reply to Michael.

Fam