Re: [musl] BUG: Calling readdir/dirfd after vfork will cause deadlock.

[Florian Weimer <fweimer@redhat.com>]

* Alex Xu:

> Excerpts from Nick Peng's message of June 24, 2022 11:40 pm:
>> Description:  After vfork, calling functions such as readdir/dirfd may
>> cause deadlock. GNU C is OK.
>
> This is not a bug. TFM:
>
> DESCRIPTION
>    Standard description
>        (From  POSIX.1)  The vfork() function has the same effect as 
>        fork(2), except that the behavior is undefined if the process 
>        created by vfork() either modifies any data other than a variable 
>        of type pid_t used to store the return value from vfork(), or 
>        returns from the function in which vfork() was called, or calls 
>        any other function before successfully calling _exit(2) or one of 
>        the exec(3) family of functions.
>
> It may happen to appear to work in some cases on some libcs, or kernels, 
> or architectures, or it may deadlock, corrupt data, or cause demons to 
> fly out your nose. Do not use vfork in this manner. Avoid using fork in 
> this manner either; that may work in musl 1.2.2+, and appear to work in 
> glibc (but sometimes randomly corrupt data), but is not portable to 
> other libcs.

Could you describe the memory corruption you have seen with
opendir/readdir on glibc?

Thanks,
Florian