Bug 3.11.x behavioral, open file buffers not flushed til file closed.

[Dieter Maurer]

aapost wrote at 2023-3-5 09:35 -0500:
> ...
>If a file is still open, even if all the operations on the file have
>ceased for a time, the tail of the written operation data does not get
>flushed to the file until close is issued and the file closes cleanly.

This is normal: the buffer is flushed if one of the following conditions
are met:
1. you call `flush`
2. the buffer overflows
3. the file is closed.