pgsql: Force pgwin32_recv into nonblock mode when called from pgstat.c.

Force pgwin32_recv into nonblock mode when called from pgstat.c.

This should get rid of the usage of pgwin32_waitforsinglesocket entirely,
and perhaps thereby remove the race condition that's evidently still
present on some versions of Windows.  The previous arrangement was a bit
unsafe anyway, since waiting at the recv() would not allow pgstat to notice
postmaster death.

Branch
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master

Details
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http://git.postgresql.org/pg/commitdiff/f1ca51549e9e7045a2db95a61744334f1dbb4d64

Modified Files
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src/backend/postmaster/pgstat.c |   12 ++++++++++++
1 files changed, 12 insertions(+), 0 deletions(-)