doc: Slightly correct advice on C/C++ linkage
The documentation was writing that <literal>extern C</literal> should
be used, but it should be <literal>extern "C"</literal>.
Branch
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master
Details
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https://git.postgresql.org/pg/commitdiff/794ba8b6a4c8ce409a37e84444c9519f7f1e5385
Modified Files
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doc/src/sgml/xfunc.sgml | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)
