Using printf (as described in the [Debugging Tips] ( is impractical on Windows because you can‘t effectively get standard I/O output from the version of sel_ldr that’s installed by default. The problem occurs because on Windows, only the debug version of sel_ldr sends output to the console. (Only the debug version is compiled with /SUBSYSTEM:CONSOLE.)

To install the debug version of sel_ldr, first build it by running .\scons.bat --mode=dbg-win. Then run .\scons.bat DBG=1 firefox_install. After the debug version is installed, a console window will appear for each instance of sel_ldr created by the browser plugin. An option that will allow redirecting the output from a Native Client module into a file is in development.

PENDING: This page should also give some tips for debugging with Visual Studio and WinDbg.