This function allows us to fsync the specified file or directory.
It's useful, for example, when we want to sync the file that
pg_file_write() writes out or that COPY TO exports the data into,
for durability.
Author: Fujii Masao
Reviewed-By: Julien Rouhaud, Arthur Zakirov, Michael Paquier, Atsushi Torikoshi
Discussion: https://www.postgresql.org/message-id/CAHGQGwGY8uzZ_k8dHRoW1zDcy1Z7=5GQ+So4ZkVy2u=nLsk=hA@mail.gmail.com
This provides a newer version of adminpack which works with the newly
added default roles to support GRANT'ing to non-superusers access to
read and write files, along with related functions (unlinking files,
getting file length, renaming/removing files, scanning the log file
directory) which are supported through adminpack.
Note that new versions of the functions are required because an
environment might have an updated version of the library but still have
the old adminpack 1.0 catalog definitions (where EXECUTE is GRANT'd to
PUBLIC for the functions).
This patch also removes the long-deprecated alternative names for
functions that adminpack used to include and which are now included in
the backend, in adminpack v1.1. Applications using the deprecated names
should be updated to use the backend functions instead. Existing
installations which continue to use adminpack v1.0 should continue to
function until/unless adminpack is upgraded.
Reviewed-By: Michael Paquier
Discussion: https://postgr.es/m/20171231191939.GR2416%40tamriel.snowman.net
Fujii Masao
Stephen Frost
Peter Eisentraut