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diff --git a/src/test/regress/input/largeobject.source b/src/test/regress/input/largeobject.source
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+--
+-- Test large object support
+--
+
+-- Load a file
+CREATE TABLE lotest_stash_values (loid oid, fd integer);
+-- lo_creat(mode integer) returns oid
+-- The mode arg to lo_creat is unused, some vestigal holdover from ancient times
+-- returns the large object id
+INSERT INTO lotest_stash_values (loid) SELECT lo_creat(42);
+
+-- NOTE: large objects require transactions
+BEGIN;
+
+-- lo_open(lobjId oid, mode integer) returns integer
+-- The mode parameter to lo_open uses two constants:
+--   INV_READ  = 0x20000 = 2 * 16^4
+--   INV_WRITE = 0x40000 = 4 * 16^4
+-- The return value is a file descriptor-like value which remains valid for the
+-- transaction.
+UPDATE lotest_stash_values SET fd = lo_open(loid, CAST((2 | 4) * 16^4 AS integer));
+
+-- loread/lowrite names are wonky, different from other functions which are lo_*
+-- lowrite(fd integer, data bytea) returns integer
+-- the integer is the number of bytes written
+SELECT lowrite(fd, '
+Whose woods these are I think I know,
+His house is in the village though.
+He will not see me stopping here,
+To watch his woods fill up with snow.
+
+My little horse must think it queer,
+To stop without a farmhouse near,
+Between the woods and frozen lake,
+The darkest evening of the year.
+
+He gives his harness bells a shake,
+To ask if there is some mistake.
+The only other sound''s the sweep,
+Of easy wind and downy flake.
+
+The woods are lovely, dark and deep,
+But I have promises to keep,
+And miles to go before I sleep,
+And miles to go before I sleep.
+
+         -- Robert Frost
+') FROM lotest_stash_values;
+
+-- lo_close(fd integer) returns integer
+-- return value is 0 for success, or <0 for error (actually only -1, but...)
+SELECT lo_close(fd) FROM lotest_stash_values;
+
+END;
+
+-- Read out a portion
+BEGIN;
+UPDATE lotest_stash_values SET fd=lo_open(loid, CAST((2 | 4) * 16^4 AS integer));
+
+-- lo_lseek(fd integer, offset integer, whence integer) returns integer
+-- offset is in bytes, whence is one of three values:
+--  SEEK_SET (= 0) meaning relative to beginning
+--  SEEK_CUR (= 1) meaning relative to current position
+--  SEEK_END (= 2) meaning relative to end (offset better be negative)
+-- returns current position in file
+SELECT lo_lseek(fd, 422, 0) FROM lotest_stash_values;
+
+-- loread/lowrite names are wonky, different from other functions which are lo_*
+-- loread(fd integer, len integer) returns bytea
+SELECT loread(fd, 35) FROM lotest_stash_values;
+
+SELECT lo_lseek(fd, -19, 1) FROM lotest_stash_values;
+
+SELECT lowrite(fd, 'n') FROM lotest_stash_values;
+
+SELECT lo_tell(fd) FROM lotest_stash_values;
+
+SELECT lo_lseek(fd, -156, 2) FROM lotest_stash_values;
+
+SELECT loread(fd, 35) FROM lotest_stash_values;
+
+SELECT lo_close(fd) FROM lotest_stash_values;
+
+END;
+
+-- lo_unlink(lobjId oid) returns integer
+-- return value appears to always be 1
+SELECT lo_unlink(loid) from lotest_stash_values;
+
+TRUNCATE lotest_stash_values;
+
+INSERT INTO lotest_stash_values (loid) SELECT lo_import('@abs_srcdir@/data/tenk.data');
+
+BEGIN;
+UPDATE lotest_stash_values SET fd=lo_open(loid, CAST((2 | 4) * 16^4 AS integer));
+
+-- with the default BLKSZ, LOBLKSZ = 2048, so this positions us for a block
+-- edge case
+SELECT lo_lseek(fd, 2030, 0) FROM lotest_stash_values;
+
+-- this should get half of the value from page 0 and half from page 1 of the
+-- large object
+SELECT loread(fd, 36) FROM lotest_stash_values;
+
+SELECT lo_tell(fd) FROM lotest_stash_values;
+
+SELECT lo_lseek(fd, -26, 1) FROM lotest_stash_values;
+
+SELECT lowrite(fd, 'abcdefghijklmnop') FROM lotest_stash_values;
+
+SELECT lo_lseek(fd, 2030, 0) FROM lotest_stash_values;
+
+SELECT loread(fd, 36) FROM lotest_stash_values;
+
+SELECT lo_close(fd) FROM lotest_stash_values;
+END;
+
+SELECT lo_export(loid, '@abs_builddir@/results/lotest.txt') FROM lotest_stash_values;
+
+\lo_import 'results/lotest.txt'
+
+\set newloid :LASTOID
+
+-- just make sure \lo_export does not barf
+\lo_export :newloid 'results/lotest2.txt'
+
+-- This is a hack to test that export/import are reversible
+-- This uses knowledge about the inner workings of large object mechanism
+-- which should not be used outside it.  This makes it a HACK
+SELECT pageno, data FROM pg_largeobject WHERE loid = (SELECT loid from lotest_stash_values)
+EXCEPT
+SELECT pageno, data FROM pg_largeobject WHERE loid = :newloid;
+
+
+SELECT lo_unlink(loid) FROM lotest_stash_values;
+\lo_unlink :newloid
+
+TRUNCATE lotest_stash_values;