Before building make sure you set environment variable NODE_PTY_DEBUG to 1 to trigger a debug build.

1. Download WinDbg: https://www.microsoft.com/en-us/p/windbg-preview/9pgjgd53tn86?rtc=1&activetab=pivot%3Aoverviewtab

2. Build and run WinDbgX.exe node .\examples\fork\index.js

3. One time setup to set paths:

   Open File > Settings, go to Debugging settings and set:

   • Source path to ...\src\win
   • Symbol path to ...\build\Debug

4. Break when pty.node is loaded:

   sxe ld pty
   

5. Go (and break at pty.node):

   g
   

6. List modules (verify pty.node is loaded):

   lm
   

7. Reload symbols:

   .reload /f
   

8. Examine a function:

   x pty!PtyStartProcess
   

   You can then open the file by clicking pty!PtyStartProcess and ...\src\win\pty.cc links. Set a breakpoint by left clicking the gutter.

9. Go:

   g
   

On Windows, you can show the winpty agent console window by adding the environment variable WINPTY_SHOW_CONSOLE=1 to the pty's environment. See https://github.com/rprichard/winpty#debugging-winpty for more information.