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Date: Wed, 11 Jun 2025 17:57:20 -0700 (PDT)
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To: Sam Edge via Cygwin <cygwin AT cygwin DOT com>
Subject: Re: Path prefix //./ in Cygwin
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On Thu, 12 Jun 2025, Sam Edge via Cygwin wrote:

> I would think that if you're building something against Cygwin, it's probably
> best to assume it's POSIX where only forward-slash is special and not try to
> second-guess.

This is unsafe, and actually where the rust PR started out.  If you only
treat '/' as special, a program may be tricked into allowing path
traversal with file/directory names like '..\..' or 'C:\Windows' which
are not path traversing or absolute paths in POSIX.

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