RFR: 8345745: Update mode of the Attach API communication pipe.

[Serguei Spitsyn]

On Thu, 29 May 2025 19:21:42 GMT, Alex Menkov <amenkov at openjdk.org> wrote:

> Please review this small fix to update pipe mode for attach operation communication.
> - `FILE_FLAG_FIRST_PIPE_INSTANCE`: there is "retry" logic if pipe creation failed [1], with this flag `CreateNamedPipe` fails when pipe with the same name already exists;
> - `PIPE_REJECT_REMOTE_CLIENTS`: attach works only for local processes, the flag adds extra protection from remote connections.
> 
> [1]: https://github.com/openjdk/jdk/blob/master/src/jdk.attach/windows/classes/sun/tools/attach/VirtualMachineImpl.java#L93
> 
> Testing: tier1..4, hs-tier5-svc

Looks good to me (according to these flags description).

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Marked as reviewed by sspitsyn (Reviewer).

PR Review: https://git.openjdk.org/jdk/pull/25530#pullrequestreview-2880909328