pgsql: Correct stdin/stdout usage in COPY .. PROGRAM

Correct stdin/stdout usage in COPY .. PROGRAM

The COPY documentation incorrectly stated, for the PROGRAM case,
that we read from stdin and wrote to stdout. Fix that, and improve
consistency by referring to the 'PostgreSQL' user instead of the
'postgres' user, as is done in the rest of the COPY documentation.

Pointed out by Peter van Dijk.

Back-patch to 9.3 where COPY .. PROGRAM was introduced.

Branch
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REL9_3_STABLE

Details
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http://git.postgresql.org/pg/commitdiff/9adda98c7738f5a8d4fdaa5a7a5bfb3f11c94899

Modified Files
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doc/src/sgml/ref/copy.sgml | 14 ++++++++------
1 file changed, 8 insertions(+), 6 deletions(-)