revid: loop mode - revid is not able to close

[Scott Barnard]

Changing a variable results in revid closing and restarting. When using loop mode, revid does not close but hangs. The message “revid: waiting for routines to close” is displayed in the logs, but revid never gets any further than this, as it gets stuck at the wait-group.

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[Scott Barnard]

Additionally, when using a filter, there will be a segfault when revid closes in loopmode. I think this is probably closely related.

[Saxon Milton]

Resolved in PR #402