Date: Thu, 6 Jan 2011 21:42:43 +0000 From: Alexander Best <arundel@freebsd.org> To: John Baldwin <jhb@freebsd.org> Cc: svn-src-head@freebsd.org, svn-src-all@freebsd.org, src-committers@freebsd.org, Konstantin Belousov <kib@freebsd.org>, Garrett Cooper <gcooper@freebsd.org> Subject: Re: svn commit: r216955 - head/usr.sbin/rtprio Message-ID: <20110106214243.GA51802@freebsd.org> In-Reply-To: <201101061618.39695.jhb@freebsd.org> References: <201101041413.p04EDA4f038360@svn.freebsd.org> <AANLkTimDTq-JXF4gm9KUfo5eJaEXKaRF-CYiycFwdZML@mail.gmail.com> <20110106211017.GA46874@freebsd.org> <201101061618.39695.jhb@freebsd.org>
next in thread | previous in thread | raw e-mail | index | archive | help
On Thu Jan 6 11, John Baldwin wrote:
> On Thursday, January 06, 2011 4:10:17 pm Alexander Best wrote:
> > On Thu Jan 6 11, Garrett Cooper wrote:
> > > On Thu, Jan 6, 2011 at 12:41 PM, Alexander Best <arundel@freebsd.org>
> wrote:
> > >
> > > ...
> > >
> > > > this causes problems when pid is -0:
> > > >
> > > > [id|rt]prio -t -0 and [id|rt]prio 10 -0 will try to run "0" via
> execvp().
> > > > beforehand however this will also trigger rtprio().
> > > >
> > > > a better solution would be to do:
> > > >
> > > > if (argv[2][0] == '-') {
> > > > proc = parseint(argv[2] + 1, "pid");
> > > > if (rtprio(RTP_SET, proc, &rtp) != 0)
> > > > err(1, "RTP_SET");
> > > > } else {
> > > > execvp(argv[2], &argv[2]);
> > > > err(1, "%s", argv[2]);
> > > > }
> > >
> > > How did you get a pid of -0?
> >
> > pid 0 stands for the current process. see rptio(2).
>
> Note that that usage is rather pointless since it means you apply rtprio to
> the 'rtprio' process that is about to exit. :)
yeah but at least it makes the usage of -X consistent. ;) also consider the
following: the current shell has idle priority and you want to run rtprio in
normal priority. then rtprio -t -0 would be a neat way of doing
rtprio -t rtprio. ;) wel...not quite, because the priotity gets set to "NORMAL"
when rtprio is almost finished running. ;)
i admit using -0 for setting rtpio's own priority isn't very useful, but the
rtprio(1) manual states:
Pid of 0 means "the current process".
...so it better work. ;)
cheers.
alex
>
> --
> John Baldwin
--
a13x
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?20110106214243.GA51802>