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From: Javi Barroso on 14 Jun 2010 07:22
On Jun 11, 2:00 am, Maxwell Lol <nos...(a)com.invalid> wrote:
> > I know but I would like to know if that is a bash bug (so should I
> > report it?) or not (because it is already known)
>
> If any process has a current directory that is deleted, then how can
> it know where its current directory is?
I don't known, but sure bash know, because if you do 'ls' files in
that directory are showed.
>
> What do you expect it to answer?
/root/to/parent #

>
> and if the current directory is unknown, what should ../ mean?
Yes, but when you do cd .. and you are in '/' then bash should know
about .. in '/' is '/' isn't it ? It is ugly have ../../../../../ #
as current pwd, isn't it ?

Regards,

From: Alan Curry on 14 Jun 2010 18:38
In article <feb294b1-fe93-42c8-92a2-89e84668614c(a)q12g2000yqj.googlegroups.com>,
Javi Barroso <javibarroso(a)gmail.com> wrote:
>On Jun 11, 2:00�am, Maxwell Lol <nos...(a)com.invalid> wrote:
>> > I know but I would like to know if that is a bash bug (so should I
>> > report it?) or not (because it is already known)
>>
>> If any process has a current directory that is deleted, then how can
>> it know where its current directory is?
>I don't known, but sure bash know, because if you do 'ls' files in
>that directory are showed.

If there are any files in a deleted directory, your filesystem is corrupted.
unmount and fsck it as soon as possible.

--
Alan Curry
From: Maxwell Lol on 14 Jun 2010 21:11
Javi Barroso <javibarroso(a)gmail.com> writes:

> On Jun 11, 2:00 am, Maxwell Lol <nos...(a)com.invalid> wrote:
>> > I know but I would like to know if that is a bash bug (so should I
>> > report it?) or not (because it is already known)
>>
>> If any process has a current directory that is deleted, then how can
>> it know where its current directory is?
> I don't known, but sure bash know, because if you do 'ls' files in
> that directory are showed.


Then we are obviously not talking about the same thing. The only way
to remove a directory is if the files in the directory are also
removed. So I don't see how files can be listed when there aren't any.

>>
>> What do you expect it to answer?
> /root/to/parent #

First of all, if this is true, then the system has changed the
current directory without you asking to change it.

And when you type "touch filename" - what happens? Are you in the
parent, or in the no-linger-existing directory?

On my system, pwd does not change, and when I try to create a file, it
says:

touch: cannot touch `filename': No such file or directory

This makes sense to me, as the directory does not exist. Having the
system changing my currect directory does not. And since any process
could remove a directory, this says that at any point in time, pwd
will change without my knowledge or permission.

I don;t believe computers should be non-deterministic.

>>
>> and if the current directory is unknown, what should ../ mean?
> Yes, but when you do cd .. and you are in '/' then bash should know
> about ..

I don't understand your point.

> in '/' is '/' isn't it ? It is ugly have ../../../../../ #
> as current pwd, isn't it ?


I don't understand. I've never seen this when I do a pwd.
From: Javi Barroso on 15 Jun 2010 02:30
On Jun 15, 12:38 am, pac...(a)kosh.dhis.org (Alan Curry) wrote:
> In article <feb294b1-fe93-42c8-92a2-89e846686...(a)q12g2000yqj.googlegroups..com>,
> Javi Barroso  <javibarr...(a)gmail.com> wrote:
>
> >On Jun 11, 2:00 am, Maxwell Lol <nos...(a)com.invalid> wrote:
> >> > I know but I would like to know if that is a bash bug (so should I
> >> > report it?) or not (because it is already known)
>
> >> If any process has a current directory that is deleted, then how can
> >> it know where its current directory is?
> >I don't known, but sure bash know, because if you do 'ls' files in
> >that directory are showed.
>
> If there are any files in a deleted directory, your filesystem is corrupted.
> unmount and fsck it as soon as possible.
Sorry, I wanted to say ls in parent directory, I'll reply last message
with an example more
From: Javi Barroso on 15 Jun 2010 02:48
On Jun 15, 3:11 am, Maxwell Lol <nos...(a)com.invalid> wrote:
> Javi Barroso <javibarr...(a)gmail.com> writes:
> > On Jun 11, 2:00 am, Maxwell Lol <nos...(a)com.invalid> wrote:
> >> > I know but I would like to know if that is a bash bug (so should I
> >> > report it?) or not (because it is already known)
>
> >> If any process has a current directory that is deleted, then how can
> >> it know where its current directory is?
> > I don't known, but sure bash know, because if you do 'ls' files in
> > that directory are showed.
>
> Then we are obviously not talking about the same thing.  The only way
> to remove a directory is if the files in the directory are also
> removed. So I don't see how files can be listed when there aren't any.
Sorry I wanted to say "in parent directory"

>
> >> What do you expect it to answer?
> > /root/to/parent #
>
> First of all, if this is true, then the system has changed the
> current directory without you asking to change it.
I expect /root/to/parent # , after chdir .. command is executed

>
> And when you type "touch filename" - what happens?  Are you in the
> parent, or in the no-linger-existing directory?
>
> On my system, pwd does not change, and when I try to create a file, it
> says:
>
>    touch: cannot touch `filename': No such file or directory
>
> This makes sense to me, as the directory does not exist.  Having the
> system changing my currect directory does not.  And since any process
> could remove a directory, this says that at any point in time, pwd
> will change without my knowledge or permission.

Yes it make sense to me too

>
> I don;t believe computers should be non-deterministic.

Of course

>
>
> >> and if the current directory is unknown, what should ../ mean?
> > Yes, but when you do cd .. and you are in '/'  then bash should know
> > about ..
>
> I don't understand your point.
>
> > in '/' is '/' isn't it ? It is ugly have ../../../../../ #
> > as current pwd, isn't it ?
>
> I don't understand. I've never seen this when I do a pwd.

You can see that in my example (in the first post)

Please see this another example, where we can see bash knows
about ../../x when current directory is deleted:

$ mkdir test ; mkdir test/test2; cd test/test2/
~/test/test2$ rmdir ../test2
~/test/test2$ bash
shell-init: error retrieving current directory: getcwd: cannot access
parent directories: No such file or directory
~/test/test2$ rmdir ../../test
~/test/test2$ ls ~/test*
ls: cannot access /home/user/test*: No such file or directory

So bash knows about parent directories

But seems like something doesn't work like expected:
~/test/test2$ # continuing with the example
~/test/test2$ cd ..
...$ ls
...$ cd ..
.../..$ ls # should I be here in ~ ?
user1 user2 user3 ... userN

Well, After all, Simply don't remove cwd, that is a stupid thing :-)

Would this be more elegant if bash could change to a well known
directory if cwd doesn't exist ?

Regards,
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