(when) does rsync daemon sync ?

[Norbert van Bolhuis]

Dear rsync-guru's,

here's a user question:

I want to make sure the files transferred to
rsync daemon (running on a linux kernel) are written to media

I assume if rsync command returns (with 0) all data has been
tranferred to rsync daemon, but it depends on the
rsync daemon priority and linux pdflush daemon before the
data is truly written to physical media (whatever that is).

Is there a way to make the rsync daemon use sync
or whatsoever to make sure the rsync command returns
only if all transferred data is written to physical media.

thanks in advance for any answers/insights

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N. van Bolhuis