From: Florian Weimer <email@example.com>
To: "Alex Xu (Hello71)" <firstname.lastname@example.org>
Subject: Re: [musl] BUG: Calling readdir/dirfd after vfork will cause deadlock.
Date: Mon, 27 Jun 2022 09:44:07 +0200 [thread overview]
Message-ID: <email@example.com> (raw)
In-Reply-To: <1656161421.nztip0vma0.none@localhost> (Alex Xu's message of "Sat, 25 Jun 2022 08:56:46 -0400")
* 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:
> 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?
next prev parent reply other threads:[~2022-06-27 7:44 UTC|newest]
Thread overview: 13+ messages / expand[flat|nested] mbox.gz Atom feed top
2022-06-25 3:40 Nick Peng
2022-06-25 12:51 ` Szabolcs Nagy
2022-06-27 4:05 ` Nick Peng
2022-06-27 10:38 ` Laurent Bercot
2022-06-27 14:21 ` Rich Felker
2022-06-27 14:29 ` Markus Wichmann
2022-06-27 7:42 ` Florian Weimer
2022-06-27 8:37 ` Szabolcs Nagy
2022-06-27 9:23 ` Florian Weimer
2022-06-27 17:33 ` Szabolcs Nagy
2022-06-25 12:56 ` Alex Xu (Hello71)
2022-06-27 7:44 ` Florian Weimer [this message]
2022-06-27 12:28 ` Alex Xu (Hello71)
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