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A comment on OpenSSH for Windows update. Parent comment

Re:OpenSSH for Windows update by antics on Monday October 19, 2015 @05:46PM (#10416015)
SUA was not half-baked, this is a very, very hard problem. There is a very serious difference in the way POSIX and Windows model a lot of really important OS primitives, from asynchronicity model in signals, to the semantics of syscalls like `fork`. Every process using these primitives on POSIX has specific behavior defined under those primitives, and if you don't choose _exactly_ the right behavior on the POSIX subsystem in Windows you will definitely break programs.

So, no. You can't "just" implement a POSIX subsystem correctly. These systems are just not compatible. It will always be half broken.

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Re:OpenSSH for Windows update by lelandbatey on Monday October 19, 2015 @07:34PM (#10416522)
Indeed. The Cygwin project has done an amazing job working to act as a compatibility layer between Windows and POSIX, but even Cygwin, with all the time and energy that's gone into it, still has some rough edges. Not to say that using it isn't awesome, but it's not perfect.
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Re:OpenSSH for Windows update by teacup50 on Monday October 19, 2015 @06:54PM (#10416348)
Microsoft does control the kernel, and given that, none of this stuff is particularly complicated.

As for choosing "_exactly_ the right behavior" ... the whole point of POSIX is to clearly define the exact right behavior!

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Re:OpenSSH for Windows update by dragonwriter on Tuesday October 20, 2015 @03:17AM (#10417867)
Sure, its "easy" if Microsoft wants to redefine Windows in POSIX terms; iits not easy to keep Windows functioning as Windows and provide a POSIX compatibility layer, since Windows isn't designed around POSIX expectations.
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Re:OpenSSH for Windows update by teacup50 on Friday October 23, 2015 @01:15PM (#10439921)
Do you actually have specifics, here? I'm happy to discuss things like how to model fork() in-kernel.
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Re:OpenSSH for Windows update by pjmlp on Tuesday October 20, 2015 @05:50AM (#10418277)
Which for everyone that has written code across UNIX systems knows it has quite some issues across systems that are supposed to share some kind of common architecture.

Even worse when the architecture is completely different.

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