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Date: Thu, 4 Jan 2024 21:28:45 +0000
From: Al Viro <viro@zeniv.linux.org.uk>
To: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Steven Rostedt <rostedt@goodmis.org>,
	LKML <linux-kernel@vger.kernel.org>,
	Linux Trace Kernel <linux-trace-kernel@vger.kernel.org>,
	Masami Hiramatsu <mhiramat@kernel.org>,
	Mathieu Desnoyers <mathieu.desnoyers@efficios.com>,
	Christian Brauner <brauner@kernel.org>,
	linux-fsdevel@vger.kernel.org,
	Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
	Jonathan Corbet <corbet@lwn.net>, linux-doc@vger.kernel.org
Subject: Re: [PATCH] tracefs/eventfs: Use root and instance inodes as default
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On Thu, Jan 04, 2024 at 11:35:37AM -0800, Linus Torvalds wrote:

> > "file description" - is how the file is accessed (position in the file and
> >                         flags associated to how it was opened)
> 
> That's a horrible term that shouldn't be used at all. Apparently some
> people use it for what is our 'struct file *", also known as a "file
> table entry".  Avoid it.

Worse, really.  As far as I can reconstruct what happened it was something
along the lines of "colloquial expression is 'opened file', but that is
confusing - sounds like a property+noun, so it might be misparsed as
a member of subset of files satisfying the property of 'being opened';
can't have that in a standard, let's come up with something else".
Except that what they did come up with had been much worse, for obvious
linguistic reasons.

The *ONLY* uses for that expression I can think of are
	1.  When reading POSIX texts, watch out for that one - if you
see them talking about a file descriptor in context where it really
should be about an opened file, check the wording.  If it really says
"file descriptOR", it's probably a bug in standard or a codified
bullshit practice.  If it says "file descriptION" instead, replace with
"opened file" and move on.
	2.  An outstanding example of the taste of that bunch.

IO channel would be a saner variant, but it's far too late for that.

The 3-way distinction between descriptor/opened file/file as collection of data
needs to be explained in UNIX 101; it is userland-visible and it has to be
understood.  Unfortunately, it's often done in a way that leaves students
seriously confused ;-/