-- 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

-- INV_READ = 0x20000

-- INV_WRITE = 0x40000

-- 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));

UPDATE lotest_stash_values SET fd = lo_open(loid, CAST(x'20000' |x'40000' AS integer));

-- loread/lowrite names are wonky, different from other functions which are lo_*

-- lowrite(fd integer, data bytea) returns integer

-- Read out a portion

BEGIN;

UPDATE lotest_stash_values SET fd=lo_open(loid, CAST((2 |4) * 16^4 AS integer));

UPDATE lotest_stash_values SET fd=lo_open(loid, CAST(x'20000' |x'40000' AS integer));

-- lo_lseek(fd integer, offset integer, whence integer) returns integer

-- offset is in bytes, whence is one of three 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));

UPDATE lotest_stash_values SET fd=lo_open(loid, CAST(x'20000' |x'40000' AS integer));

-- with the default BLKSZ, LOBLKSZ = 2048, so this positions us for a block

-- edge case

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

-- INV_READ = 0x20000

-- INV_WRITE = 0x40000

-- 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));

UPDATE lotest_stash_values SET fd = lo_open(loid, CAST(x'20000' |x'40000' 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

END;

-- Read out a portion

BEGIN;

UPDATE lotest_stash_values SET fd=lo_open(loid, CAST((2 |4) * 16^4 AS integer));

UPDATE lotest_stash_values SET fd=lo_open(loid, CAST(x'20000' |x'40000' 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

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));

UPDATE lotest_stash_values SET fd=lo_open(loid, CAST(x'20000' |x'40000' 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;