Re: [PATCH] xs: set read_thread stacksize

[Ian Campbell <Ian.Campbell@citrix.com>]

On Wed, 2012-05-30 at 08:56 +0100, Simon Rowe wrote:
> On Tuesday 29 May 2012 20:39:33 Ian Campbell wrote:
> 
> > ...and if it were then autoconf is the way to figure that out now,
> > unless _POSIX_THREAD_ATTR_STACKSIZE is specified somewhere (which I
> > doubt).
> 
> I was following the recommendation of the POSIX Threads: Semi-FAQ which states
> 
> 
> 5.2 How can I determine if a system supports the Stack Attribute(s)?
> 
> If the header file unistd.h defines the symbolic constant  
> _POSIX_THREAD_ATTR_STACKSIZE to a value greater than 0, the implementation 
> should support the getting and setting of the Stack Size Attribute. If it 
> defined to a value of 200112L then the current specification is supported.
> 
> 
> If this needs to be done via autoconf let me know.

If this little trick applies to both NetBSD and uclibc too then I guess
it would be OK, otherwise I think autoconf is necessary.

> > Also if it is only pthread_attr_setstacksize which is optional, rather
> > than pthread_attr_* generally, then the #if could be pulled into just
> > surround that call, presuming there is no harm in a "NULL" attr.
> 
> I don't quite get you, do you mean only protect the actual 
> pthread_attr_setstacksize() call with #ifdef and therefore always call 
> pthread_attr_init()?

Yes, that'll reduce the ifdeffery and inparticular removes the double
	if (pthread_create(&h->read_thr, NULL, read_thread, h) != 0) {
in either half, which is bit tricky to follow and is going to be prone
to drift across the two sides.