Subject: Re: ptrace(2) + nathanw_sa LWPs
To: None <thorpej@wasabisystems.com>
From: Nathan J. Williams <nathanw@MIT.EDU>
List: tech-kern
Date: 12/08/2001 12:46:03
Jason R Thorpe <thorpej@wasabisystems.com> writes:

> On Sat, Dec 08, 2001 at 02:23:13PM +1100, Giles Lean wrote:
> 
>  > Is it interesting to compare what other operating systems have done?
>  > HP-UX introduced ttrace(2) to overcome the limitations of ptrace(2)
>  > with multithreaded processes, and HP contributed changes to gdb to
>  > enable it to use ttrace(2).
>  > 
>  > http://docs.hp.com//hpux/onlinedocs/B2355-90682/00/02/219-con.html
> 
> I'll take a look at this.

A quick scan makes this look pretty reasonable - they add another
argument to the call to identify a LWP, and they also provide a
mechanism for iterating over LWPs. PT_{GET,SET}_LWP commands are
tricky if you don't know which LWP IDs are valid.....


> Solaris does everything via its procfs.

And hence gets to use the directory for iteration.

        - Nathan