> in a directory that has subdirectories? It will open the directory
> (because right now we allow it to happen even without O_DIRECTORY), but
> then when it reads it will get an error and will print out
Introducing default files will break fstat(2).
> grep: yyyy: Is a directory
>
> which is obviously just not what the user meant.
Interesting to note how stupid grep really is:
open("acpi", O_RDONLY) = 4
fstat(4, {st_mode=S_IFDIR|0775, st_size=1024, ...}) = 0
read(4, 0x8060000, 32768) = -1 EISDIR (Is a directory)
[lstat() returns file, file is exchanged by a directory until the open()
happens]
> So what's the problem? You expected to open a file, and you opened a file.
> that can happen today. The fact that somebody renamed something from under
> you meant that you got a different file than the one you thought you'd
> get, but that is exactly the behaviour you have today.
A real problem, however, is that fstat() does not allow you to check
whether you just opened a link. Maybe a solution would be to add an
O_NOLINK flag that makes open refuse to open a symlink (that is not root
owned?)?
Simon
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