Fix the conformance of poll(2) for sockets after r195423 by
returning POLLHUP instead of POLLIN for several cases. Now, the
tools/regression/poll results for FreeBSD are closer to that of the
Solaris and Linux.
Also, improve the POSIX conformance by explicitely clearing POLLOUT
when POLLHUP is reported in pollscan(), making the fix global.
Submitted by: bde
Reviewed by: rwatson
MFC r196556
Fix poll() on half-closed sockets, while retaining POLLHUP for fifos.
This reverts part of r196460, so that sockets only return POLLHUP if both
directions are closed/error. Fifos get POLLHUP by closing the unused
direction immediately after creating the sockets.
The tools/regression/poll/*poll.c tests now pass except for two other
things:
- if POLLHUP is returned, POLLIN is always returned as well instead of
only when there is data left in the buffer to be read
- fifo old/new reader distinction does not work the way POSIX specs it
Reviewed by: kib, bde
MFC r196554
Add some tests for poll(2)/shutdown(2) interaction.
Approved by: re (kensmith)
