Changing the name of the directory I am in

fieldmethods · 01-05-2004, 11:13 PM

Hi,

Here's a typescript of something I find... flummoxing.

Code:

$ # Whoa, this is weird. I'm in home sweet home... 
$ pwd
/home/me
$ # I make a directory "baz":
$ mkdir baz
$ cd baz
$ # Okay, here we are.
$ pwd
/home/me/baz
$ # I rename "baz" to "qux" while still in "baz"...
$ mv ../baz ../qux
$ pwd
/home/me/baz
$ # Huh? I thought I was in "qux" now!
$ cd ..
$ cd baz
bash: cd: baz: No such file or directory
$ # Now it's gone?
$ cd qux
$ pwd
/home/me/qux
$ # But "qux" exists. That is weird.

Why does "baz" not show up as "qux" until I reenter the directory?

Cheers,
pat

samhob · 01-05-2004, 11:49 PM

cd ../qux

itsjustme · 01-05-2004, 11:50 PM

I don't think that's weird.
Though I have no technical data to back me up.
But, probably, since you are in that directory and it's active, it can't just change willy nilly right out from under you. It apparently maintains its identity until the 'session' is released.

fieldmethods · 01-08-2004, 03:43 PM

Thanks for the replies.

Yeah, I guess "weird" is the wrong word... more like "interesting."

The issue, as I see it, is "when is the name of the current working directory set?" I presume the answer to that is pretty low-level, kernel-level stuff.

Come to think about it, I should reproduce the sequence of commands in different shells, and maybe from a Perl script, to see if I could come up with a different result.

Fun.

Cheers,
Pat

Tinkster · 01-08-2004, 04:07 PM

Try a cd . and then look at $PWD ...

Only a cd actually re-evaluates the
current directory and sets PWD...

Cheers,
Tink