On Wed, 20 Nov 2019 at 13:10, Amit Kapila <amit.kapila16@gmail.com> wrote: > See comment in pgunlink() "We need to loop because even though > PostgreSQL uses flags that allow unlink while the file is open, other > applications might have the file > open without those flags.". Can you once see if there is any flag > that you have missed to pass to allow this?
> If there is nothing we > can do about it, then we might need to use some different API or maybe > define a new API that can handle this.
There were objections against modifying the vfd api only for this replication-related use-case. Having a new API will require all the changes required to enable the virtual FDs feature that we need from vfd. If nothing works out from the FILE_SHARE_DELETE thing, I am thinking, we can use VFD, plus we can keep track of per-subtransaction vfd handles, and do something similar to AtEOSubXact_Files().
The comment about "other applications might have the file open without those flags." is surely due to systems working with an antivirus touching Postgres files.
I was not able to reproduce the Permission denied error with current HEAD, until I opened another CMD inside the "pg_replslot/regression_slot" folder. This will be problematic, is the deletion of the folder actually needed?