Can't use read-only index mount with latest version

[niklas88]

After the changes in #214 one can no longer mount the index read-only e.g. when using docker … -v $(pwd)/index:/index:ro

It throws the following exception:

terminate called after throwing an instance of 'ad_utility::TruncateException'
  what():  truncating of file /index/wikidata-2019-02-26.index.spo.meta-mmap to size 36529975296set errno to30 terminating

[joka921]

@niklas88 I think this should be fixed by now, so we should be safe to close?

[niklas88]

Yes this is fixed