pgsql: Don't use EV_CLEAR for kqueue events.

Don't use EV_CLEAR for kqueue events.

For the semantics to match the epoll implementation, we need a socket to
continue to appear readable/writable if you wait multiple times without
doing I/O in between (in Linux terminology: level-triggered rather than
edge-triggered).  This distinction will be important for later commits.
Similar to commit 3b790d256f8 for Windows.

Reviewed-by: Kyotaro Horiguchi <horikyota.ntt@gmail.com>
Discussion: https://postgr.es/m/CA%2BhUKGJAC4Oqao%3DqforhNey20J8CiG2R%3DoBPqvfR0vOJrFysGw%40mail.gmail.com

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/9b8aa0929390aab1f2f0859016e6110d283732dd

Modified Files
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src/backend/storage/ipc/latch.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)