[pgpool-committers: 5899] pgpool: Backport Pgversion().

[Tatsuo Ishii]

Backport Pgversion().

Branch
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V4_0_STABLE

Details
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https://git.postgresql.org/gitweb?p=pgpool2.git;a=commitdiff;h=a5d8f05642714059af99c8a7fd95b23e88c8a57f

Modified Files
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src/include/pool.h   |  19 ++++++-
src/protocol/child.c | 157 ++++++++++++++++++++++++++++++++++++++++++++++++++-
2 files changed, 173 insertions(+), 3 deletions(-)