Is there a way to open BerkeleyDB exclusive?
What is your intended goal?
If it is to prevent two bitcoin clients from actively using the same database, you’ll need to employ application-level protection. Crude methods of this include a lockfile or “lock” database entry.
If the intention is to prevent all other access, I’d suggest giving up on that goal 😊 It is highly useful to permit db4 tools to access db4 databases:Code:db46_archive db46_deadlock db46_load db46_stat db46_checkpoint db46_dump db46_printlog db46_upgrade db46_codegen db46_hotbackup db46_recover db46_verify and just as useful to permit read-only accesses by tools such as gavin’s bitcointools.