:: Re: [DNG] OT: redirecting piped / p…
Página Inicial
Delete this message
Reply to this message
Autor: Florian Zieboll
Data:  
Para: [DNG]
Assunto: Re: [DNG] OT: redirecting piped / processed stderr to a file
On Mon, 14 Mar 2022 22:25:51 +0100
Ludovic Bellière <belliere.ludovic@???> wrote:

> On Mon, 14 Mar 2022, Florian Zieboll via Dng wrote:
>
> [...]
> >
> >So I assume that it is 'tr' which recognizes that rsync's output is
> >already buffered and thus keeps this setting - while the output of
> >'dd' comes in another format and 'tr' decides that it would be a
> >good idea to 4k-buffer it before passing it on?
> >
>
> The 4k buffer would be the "default", which may differ per system.
> Reading the man page (again) tells me that the default pipe capacity
> is 16 pages (65,536 bytes in a system with a page size of 4096
> bytes). The 4k buffer thing was valid for old kernels.
>
> >
> [...]
> >
> >Yes, unbuffering the input of 'tr' (from 'dd') does not have any
> >effect.
>
> There's probably buffer between 'rsync' and 'tr'. Checkout the
> documentation for 'rsync --outbuf=N|L|B'.



Hallo Ludovic,

I probably found the (very trivial) reason that only dd's output got
"stuck" in the buffer: rsync seems to refresh its status much more
often, haha!

Thanks for your advice and libre Grüße,
Florian