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From: David Xu <davidxu@freebsd.org>
To: gnn@freebsd.org
Date: Tue, 31 Oct 2006 07:18:15 +0800
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Subject: Re: libthr status
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On Tuesday 31 October 2006 02:23, gnn@freebsd.org wrote:
> > I will hack at kernel side, but who will hack userland utilities ?
> > e.g the /usr/bin/limits program.
>
> How hard is that to do?  If it's "easy" then I can sign up to do that.
>

I think it is not hard, but I think one at least has to hack /usr/bin/limits,
sh and csh which are in our base system.

> > > > 2) Things can only be used by root:
> > > >
> > > > 2.1) the real-time scheduling options can only be used by root, e.g,
> > > > if you call pthread_attr_setschedpolicy() with parameter SCHED_FIFO
> > > > or SCHED_RR, the thread can only be created by root, normal user
> > > > will get EPERM errno. you can use it in libpthread, but it is not
> > > > real-time, it is a static priority scheduling in userland scheduler,
> > > > if you want to preemptable other threads or processes in the system
> > > > when playing real-time multimedia or military program, no way!
> > > >
> > > > 2.2) the real-time scheduling is not safe, it can deadlock itself and
> > > > the whole system if program behavors incorrectly, it should only be
> > > > used by trusted programs.
> > >
> > > Are these (can these be) documented in the man pages?
> >
> > No, they are not documented.
>
> If these limitations will be there for a while can you update the man
> page?  If you like I can review that change for correctness.
>
> Best,
> George

I will update them and make them reviewed.

Thanks,
David Xu