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From: Keith Thompson <Keith.S.Thompson+u@gmail.com>
Newsgroups: comp.lang.c
Subject: Re: encapsulating directory operations
Date: Tue, 20 May 2025 22:49:01 -0700
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Kaz Kylheku <643-408-1753@kylheku.com> writes:
> On 2025-05-20, Keith Thompson <Keith.S.Thompson+u@gmail.com> wrote:
>> "Paul Edwards" <mutazilah@gmail.com> writes:
[...]
>>> As far as I know, there was never any LOGICAL barrier
>>> to including basic directory manipulation in C90.
>>
>> None that I can think of.
>
> There was a significant barrier. The ANSI group which standardized
> C was mainly looking at surveying and codifying existing practice.

Agreed.  I consider that a practical barrier, not a "LOGICAL" one.

The ANSI C committee *could* have added directory operations to the C
standard library.  (I'm not suggesting that they should have.)

[...]

>> Sure, it would be theoretically possible to treat directories as files,
>> and to make reading from a FILE* resulting from calling fopen() with a
>> directory name give you access to the directory entries.
>
> I implemented something like this. It is fine; I don't regret it.
>
> i1> (open-directory ".")
> #<dir-stream b7b90820>
> 2> (get-line *1)
> "htrailer.txr"
> 3> (get-line *1)
> "y.output.bison"
> 4> (get-line *1)
> "jmp.S"
> 5> (open-file "/etc/hosts")
> #<file-stream /etc/hosts b7b7a8b0>
> 6> (get-line *5)
> "127.0.0.1\tlocalhost"
> 7> (get-line *5)
> "127.0.1.1\tsun-go"

It looks like it treats a directory as a file containing a
sequence of *lines*, each of which is a file name.  The problem
with that is that on some systems, file names can legally include
newline characters.  I don't suggest it's not a horrible idea to
take advantage of that, but it is something that would have to be
addressed in a language standard.

[...]

-- 
Keith Thompson (The_Other_Keith) Keith.S.Thompson+u@gmail.com
void Void(void) { Void(); } /* The recursive call of the void */