Initialise read only store

[dpajkovic]

Hello,

I'm certain I'm doing something stupid since this is turning up with error, but I'm trying to open a read only store by passing the options to the bolthold.Open function:

var bho bolthold.Options
bho.ReadOnly = true

store, err := bolthold.Open(dbFilename, fs.FileMode(os.O_RDONLY), &bho)

And it always errors out on the second line with "runtime error: invalid memory address or nil pointer dereference". Please help this newb 😄

TIA

[timshannon]

I can replicate. It may be a bug, as this is something I've never attempted and I may be making some assumptions how index handling.

Thanks for the reporting.

[timshannon]

So the issue has nothing to do with ReadOnly or not, it has to do with the fact that I'm (likely incorrectly) using a pointer to the bbolt options inside my BoltHold options.

It's probably more correct to not structurally inherit the field values as a pointer for this very reason, however changing it now would require a major semver change since these options are a exported struct.

You can work around it for now by instantiating the internal bolt.Options:

	bho := &bolthold.Options{
		Options: &bolt.Options{
			ReadOnly: true,
		},
	}