diff --git a/Documentation/Debugger/gdb/Windows Subsystem for Linux.md b/Documentation/Debugger/gdb/Windows Subsystem for Linux.md new file mode 100644 index 0000000000..929d6c5d44 --- /dev/null +++ b/Documentation/Debugger/gdb/Windows Subsystem for Linux.md @@ -0,0 +1,86 @@ +# Windows 10's Windows Subsystem for Linux +With the release of Windows 10 Creators Update, you will now be able to use Visual Studio Code and the Microsoft C/C++ extension to debug your `Windows Subsystem for Linux (WSL)` [Bash on Ubuntu](https://msdn.microsoft.com/en-us/commandline/wsl/about) projects. + +Code can be written on Windows itself using VSCode and debugged through `bash.exe` to the Bash on Windows layer. + +**NOTE: Creator's Update is required due to bugfixes within the subsystem that we rely on to provide debugging. Debugging using a previous version of WSL is unsupported and likely will not work.** + +## Prerequisites +* [Windows 10 Creators Update with Windows Subsystem for Linux and Bash](https://msdn.microsoft.com/en-us/commandline/wsl/install_guide) installed. +* Install g++/gcc and gdb within `WSL` to allow compiling and debugging. You can use the package manager to do this. For example, to install g++, you can run `sudo apt install g++` in the Bash window. +* [Visual Studio Code](https://code.visualstudio.com) + Microsoft C/C++ extension for VSCode. + +## How-To +To debug, commands will be routed from Windows through `bash.exe` to set up debugging. Because our extension runs as a 32-bit process, it will need to use the `C:\Windows\SysNative` folder to access the `bash.exe` executable that is normally in `C:\Windows\System32`. We will be using the `"pipeTransport"` ability within the extension to do debugging and `"sourceFileMap"` to map the source from the subsystem's paths back to Windows path. + +**NOTE: Applications will need to be compiled in the `Windows Subsystem for Linux (WSL)` prior to debugging.** + +### Example `launch.json` for Launching + +In the following example, I have a local drive, `Z:\` that has my source code within windows for an app called kitchensink. I have set up the `"program"` and `"cwd"` paths to point to the directory within `WSL`. I have set up the `"pipeTransport"` to use `bash.exe`. I have also set up a `"sourceFileMap"` to have everything that is returned by `gdb` that starts with `/mnt/z` to point to `Z:\\` in Windows. + +``` + { + "name": "C++ Launch", + "type": "cppdbg", + "request": "launch", + "program": "/mnt/z/Bash/kitchensink/a.out", + "args": ["-fThreading"], + "stopAtEntry": false, + "cwd": "/mnt/z/Bash/kitchensink", + "environment": [], + "externalConsole": true, + "windows": { + "MIMode": "gdb", + "setupCommands": [ + { + "description": "Enable pretty-printing for gdb", + "text": "-enable-pretty-printing", + "ignoreFailures": true + } + ] + }, + "pipeTransport": { + "pipeCwd": "", + "pipeProgram": "c:\\windows\\sysnative\\bash.exe", + "pipeArgs": ["-c"], + "debuggerPath": "/usr/bin/gdb" + }, + "sourceFileMap": { + "/mnt/z": "z:\\" + } + } +``` + +### Example `launch.json` for Attaching to an Existing Process + +This configuration similar to the launch process above. I have chosen to start the same application above from the Bash command line and now I want to attach to it for debugging. I have changed the `"processID"` to use the remote process picker by specifying the command `"${command:pickRemoteProcess}"` and set up the same `"sourceFileMap"`. When I press F5 to attach, I get a picker drop down showing the running processes within `WSL`. I can scroll or search for the process I want to attach to and start debugging. + +``` + { + "name": "C++ Attach", + "type": "cppdbg", + "request": "attach", + "program": "/mnt/z/Bash/kitchensink/a.out", + "processId": "${command:pickRemoteProcess}", + "windows": { + "MIMode": "gdb", + "setupCommands": [ + { + "description": "Enable pretty-printing for gdb", + "text": "-enable-pretty-printing", + "ignoreFailures": true + } + ] + }, + "pipeTransport": { + "pipeCwd": "", + "pipeProgram": "c:\\windows\\sysnative\\bash.exe", + "pipeArgs": ["-c"], + "debuggerPath": "/usr/bin/gdb" + }, + "sourceFileMap": { + "/mnt/z": "z:\\" + } + } +``` \ No newline at end of file