How Free software licenses apply to "Bash comes to Windows 10" scenario?


We recently heard that Bash is coming to Windows 10 not just as a software but a native one. Here’s the quote,

“This is not a VM. This is not cross-compiled tools. This is native,”

  • Kevin Gallo, Microsoft

So, this got me into thinking about how Free software licenses would play out in this scenario. I will start by saying what would happen when developer-1 is creating a software product (Free software) and adds some proprietary software/library created by developer-2 to his product,

  • If developer-1 had purchased the software/library from developer-2, then all goes well
  • But, if developer-1 just uses the software/library without paying developer-2, then he is into serious copyright violation

Now, we know that in GPL , if any software is using another GPL software/library, then that software should follow suit. Keeping this in mind, lets come to the main reason which this post is based on. Microsoft is integrating bash within Windows 10, as many of the bash tools are created with various Free/Open Source licenses, the following questions are,

  • How those rules would apply in this scenario?
  • Is Microsoft choosing tools that doesn’t give them any legal trouble
  • Or to avoid trouble, are they rewriting those tools

Any insights on this topic is appreciated.

Link to the news:

Similar question in Quora:


I don’t know if Bash is being “integrated” by linking it into existing proprietary software. I think it’s merely “included” in Windows and the operating system was tweaked to help Bash run CPU cycles. All software that actually use Bash by linking to it (none as far as I know) need to be GPL or protected by the GPL linking exception

Programs like apt-get use Bash without linking to it which means, Bash invokes those programs by itself when you type the commands. This makes Bash a stand alone GPL v3 application without violating any licenses.

I might have missed something but this is what I think given all the info available about this integration.


its is more appropriate to call “GNU/windows”, isn’t it?


@samdraz agreed 100%


you can’t call it that yet since GNU is not a large part of Windows. Windows will still be a complete operating system without any GNU tainted software.