Bash on Ubuntu on Windows Taiwan Evolutionary Intelligence Laboratory Lin, Yuen-Jen

Outline Background Architecture Technical details Demo

Background Threatened in developer market by Linux and Mac OS X Cooperate with Canonical From project Astoria (abandoned), which originated to run Android apps on Windows 10

Background Bash on Ubuntu on Windows: Service that users can use Linux on Windows Windows Subsystem for Linux (WSL): the function build in Windows that Bash on Ubuntu on Windows relies on.

Architecture

Architecture User mode session manager Pico sessions Pico drivers

Architecture Linux Application Windows Application Pico Driver NT kernel

Technical details Pico process Pico Drivers File systems

Pico process Decouple OS dependencies from the underlying host OS Run in the “library OS” Separate the host OS from trying to manage the user- mode address space inside it. When Windows kernel detect system calls from a pico process, it passes to pico provider to handle.

Pico Process

Pico drivers Difference between Linux and Windows: System calls, Application Binary Interface (ABI) What Pico drivers have to do: Transfer Linux system calls to Windows system calls Pass the parameters using the registers defined by the Linux ABI

Pico drivers

File Systems Linux uses the Virtual File System (VFS) VolFs: the file system designed to emulate VFS in WSL. DrvFs: designed to facilitate interoperability with Windows. Windows drives, such as C: and D:, are mounted under /mnt.

File Systems

Demo

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What is different from containers Translation between different syscall systems Different level of separation

Conclusion New way for using Linux on Windows machine Looks powerful but limits exist

Reference WSL blog, https://blogs.msdn.microsoft.com/wsl/ Image source: WSL blog http://en.community.dell.com/techcenter/os- applications/w/wiki/6950.lxc-containers-in-ubuntu- server-14-04-lts