bug or feature in userland thread library (O_NONBLOCK)

[David Xu]

Luigi Rizzo wrote:

>Probably a known issue, but I thought it worthwhile reporting it,
>if nothing else for archival purposes.
>
>I think our userland thread library (libc_r) has some bugs in
>handling descriptors.  I can reproduce the behaviour on -current
>and 4.x, and I believe it applies to 5.x too.  
>
>Following is a description of the problem and some code to replicate it
>The code includes a workaround but it is not particularly nice.
>
>Any better ideas ? I am not sure on what to do, but perhaps the
>only sensible thing to do is to add a note with this workaround
>(or better ones, if available) to our pthreads manpage
>
>  
>
libc_r is deprecated on -CURRENT,  I think start from 6.0, libc_r really
should be moved to ports. ;)

David Xu