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Date:   Fri, 13 Mar 2020 16:34:25 +0900
From:   Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com>
To:     Bruno Meneguele <bmeneg@redhat.com>
Cc:     linux-kernel@vger.kernel.org, stable@vger.kernel.org,
        pmladek@suse.com, sergey.senozhatsky@gmail.com, rostedt@goodmis.org
Subject: Re: [PATCH] kernel/printk: add kmsg SEEK_CUR handling
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On (20/03/12 21:35), Bruno Meneguele wrote:
> 
> Userspace libraries, e.g. glibc's dprintf(), expect the default return value
> for invalid seek situations: -ESPIPE, but when the IO was over /dev/kmsg the
> current state of kernel code was returning the generic case of an -EINVAL.
> Hence, userspace programs were not behaving as expected or documented.
> 

Hmm. I don't think I see ESPIPE in documentation [0], [1], [2]

[0] https://pubs.opengroup.org/onlinepubs/9699919799/functions/fprintf.html
[1] http://man7.org/linux/man-pages/man3/dprintf.3p.html
[2] http://man7.org/linux/man-pages/man3/fprintf.3p.html

	-ss