Re: Weird Error Using Euphoria Database System (EDS)
- Posted by petelomax Jun 12, 2018
- 1271 views
ghaberek said...
Here's the test code I threw together. Using DB_LOCK_SHARED for db_open() causes it to crash with "wrong file mode for attempted operation" as you're getting. If you switch to DB_LOCK_EXCLUSIVE, it works fine.
-- -- DB_LOCK_NO : works -- DB_LOCK_SHARED : fails -- DB_LOCK_EXCLUSIVE : works --
Same on Phix (thanks Greg for making that test super-easy).
The OE and Phix docs for db_open() both state:
Parameters: lock_method : DB_LOCK_SHARED : (shared lock for read-only access) DB_LOCK_SHARED is only supported on Unix platforms. It allows you to read the database, but not write anything to it.
I don't know if the Unix-only bit is still true (I might try testing it tomorrow), but otherwise that agrees with this result.
However the docs (both OE and Phix) go on to say:
If you request DB_LOCK_SHARED on WINDOWS it will be treated as if you had asked for DB_LOCK_EXCLUSIVE.
yet I cannot see anything to support that claim in the source code of db_open(), and this case, on Windows, it has patently not worked the same as DB_LOCK_EXCLUSIVE.
Are we all in agreement that last sentence should just be deleted?
Pete
