Thread: pgsql: doc: correct description of libpq's PQsetnonblocking() mode

doc:  correct description of libpq's PQsetnonblocking() mode

Reported-by: Yugo NAGATA

Discussion: https://postgr.es/m/20210713115949.702986955f8ccf23fa81073c@sraoss.co.jp

Backpatch-through: 12-16, master already done

Branch
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REL_16_STABLE

Details
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https://git.postgresql.org/pg/commitdiff/4b48770aeb6dd83df09e1a73dc111850ba19762c

Modified Files
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doc/src/sgml/libpq.sgml | 7 ++++---
1 file changed, 4 insertions(+), 3 deletions(-)