On Thu, Dec 09, 1999 at 05:41:09PM -0500, Daniel Eischen wrote:
> Richard Seaman, Jr. wrote:
> > Actually, I don't think all that many apps use pthread_cancel().
> > Its kind of messy to use. Most can get along without it, which
> > is why there have only been a limited number of complaints about
> > the lack of pthread_cancel() in libc_r (until recently). BTW,
> > I haven't looked at libc_r's new cancellation functions. How do
> > they avoid propagating cancellation points in libc without
> > changing libc? Maybe they have an idea that can be used here?
>
> Hi Richard,
>
> Libc_r doesn't avoid propagating cancellation points. A read()
> from within a libc(_r) function will still be a cancellation
> point.
Hmm..
What happens with (for example) fread() ?
fread, in the thread safe version, can be:
lock FILE pointer
read
unlock FILE pointer
If fread is a cancellation point, don't you end up with
the lock held still? Or, I guess since you keep track of
lock owners you can unwind the locks if the thread cancels?
--
Richard Seaman, Jr. email: [EMAIL PROTECTED]
5182 N. Maple Lane phone: 262-367-5450
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