Re: mkdir -p competition on the same directory?

[Pádraig Brady]

On 09/02/2023 16:28, Peng Yu wrote:
> OK.
>
> I see the following output of `sudo dtruss mkdir -p d`. So
> essentially, coreutils first calls system function mkdir to make the
> directory. On error of the system call, it will check the target is a
> directory. If the target is indeed a directory, then no error message
> will be printed. Do I understand it correctly?
>
> ...
> mkdir("d\0", 0x1FF, 0x0)     = -1 Err#17
> stat64("d\0", 0x7FFEE9953D20, 0x0)     = 0 0
> ...
>
> Therefore, when there is competition among many calls to coreutils
> `mkdir -p`. The first instance will create the target, and the rest
> instances will fail on the system call of mkdir. But since they find
> the target is already created and is a directory, they will not
> complain about the error system call mkdir. That is why I never see an
> error similar to that of bash loadable `mkdir -p`. Is it so?

Right. That suggests a bug in the bash loadable,
as it should not fail in this case.

cheers,
Pádraig