bug#18851: 24.4; emacs cannot be started if the current directory has been removed

[Eli Zaretskii]

> From: Andreas Schwab <schwab@suse.de>
> Cc: Vincent Lefevre <vincent@vinc17.net>,  18851@debbugs.gnu.org
> Date: Wed, 29 Oct 2014 16:39:22 +0100
> 
> > AFAIK, GNU/Linux does the former.  The directory is not physically
> > removed until the last process that has an open file descriptor for it
> > closes that descriptor.  Any attempts to reference that directory for
> > obtaining a new descriptor will get ENOENT, i.e. the OS pretends that
> > the directory doesn't exist.  But existing descriptors are valid, and
> > can be used as usual.
> 
> "As usual" is an exaggeration.  Basically the only valid operations on
> it are fstat and fchdir.  Any attempt at adding an entry to it (via
> openat) will be rejected.

Yes, any attempt to add descriptors will fail.  By "as usual" I meant
using the descriptor to extract information, like fstat, readdir, etc.