pgsql: doc: document how the backup manifest is transferred

doc: document how the backup manifest is transferred

Reported-by: Bernd Helmle

Discussion: /messages/by-id/31acf8b0f1f701d53245e0cae38abdf5c3a0d559.camel@oopsware.de

Backpatch-through: 13

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/ab3c6d41552411ea2fe4904ec8294951c52c113d

Modified Files
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doc/src/sgml/protocol.sgml | 6 ++++--
1 file changed, 4 insertions(+), 2 deletions(-)