GNU bug report logs - #27803
dd by default prints output to stderr instead of stdout

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Message #5 received at submit <at> debbugs.gnu.org (full text, mbox):

From: vasanth kumar <cvasanth2707 <at> gmail.com>
To: bug-coreutils <at> gnu.org
Subject: dd by default prints output to stderr instead of stdout
Date: Mon, 24 Jul 2017 20:04:27 +0530

[Message part 1 (text/plain, inline)]

Hi,

When I run a dd command successfully, it actually  prints I/O statistics to
standard error and not stdout . Is not it suppposed to print it on stdout
by default for a good run?

Thanks,
Vasanth

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Message #12 received at 27803-done <at> debbugs.gnu.org (full text, mbox):

From: Eric Blake <eblake <at> redhat.com>
To: vasanth kumar <cvasanth2707 <at> gmail.com>, 27803-done <at> debbugs.gnu.org
Subject: Re: bug#27803: dd by default prints output to stderr instead of stdout
Date: Mon, 24 Jul 2017 10:13:20 -0500

[Message part 1 (text/plain, inline)]

tag 27803 notabug
thanks

On 07/24/2017 09:34 AM, vasanth kumar wrote:
> Hi,
> 
> When I run a dd command successfully, it actually  prints I/O statistics to
> standard error and not stdout . Is not it suppposed to print it on stdout
> by default for a good run?

No, POSIX requires that it print stats to stderr.
http://pubs.opengroup.org/onlinepubs/9699919799/utilities/dd.html
"STDERR

    On completion, dd shall write the number of input and output blocks
to standard error...."

Therefore, the behavior is intentional, and I'm closing this as not a
bug.  However, feel free to reply to this thread if you have further
questions on the topic.

-- 
Eric Blake, Principal Software Engineer
Red Hat, Inc.           +1-919-301-3266
Virtualization:  qemu.org | libvirt.org

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Message #15 received at 27803-done <at> debbugs.gnu.org (full text, mbox):

From: vasanth kumar <cvasanth2707 <at> gmail.com>
To: Eric Blake <eblake <at> redhat.com>
Cc: 27803-done <at> debbugs.gnu.org
Subject: Re: bug#27803: dd by default prints output to stderr instead of stdout
Date: Mon, 24 Jul 2017 20:49:29 +0530

[Message part 1 (text/plain, inline)]

Thanks Eric .I got the answer.

On Mon, Jul 24, 2017 at 8:43 PM, Eric Blake <eblake <at> redhat.com> wrote:

> tag 27803 notabug
> thanks
>
> On 07/24/2017 09:34 AM, vasanth kumar wrote:
> > Hi,
> >
> > When I run a dd command successfully, it actually  prints I/O statistics
> to
> > standard error and not stdout . Is not it suppposed to print it on stdout
> > by default for a good run?
>
> No, POSIX requires that it print stats to stderr.
> http://pubs.opengroup.org/onlinepubs/9699919799/utilities/dd.html
> "STDERR
>
>     On completion, dd shall write the number of input and output blocks
> to standard error...."
>
> Therefore, the behavior is intentional, and I'm closing this as not a
> bug.  However, feel free to reply to this thread if you have further
> questions on the topic.
>
> --
> Eric Blake, Principal Software Engineer
> Red Hat, Inc.           +1-919-301-3266
> Virtualization:  qemu.org | libvirt.org
>
>

[Message part 2 (text/html, inline)]

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