Re: error and program_name

[Paul Eggert]

On 12/22/2010 03:32 PM, Bruno Haible wrote:
> For example, if save_cwd called
>   currdir_fd = open (".");
> then on a platform that supports fchdir() natively [not gnulib's
> emulation], a failure to do  fchdir (currdir_fd)  is of type (a).
> It can only occur if some other part of the program did side
> effects on currdir_fd.

Hmm, well, no, the fchdir could also fail if the directory is
on a remote file system and the network is down.  Or
if there is an I/O error (errno == EIO).  Or if search
permission is absent from the directory, assuming the
usual case where the directory was opened with O_RDONLY.
There are probably other reasons.

One workaround would be to wrap every system call
that resolves file names, so that all of these system calls
fail if given a relative file name after the fchdir failed.
But that sounds pretty drastic.