Abraham Karplus added the comment:
I'd be fine with having it fixed just in 3.4, as it is easy enough to work
around for now. (Call deletecommand('exit') and then createcommand('exit',
working_exit_function) with working_exit function being the patched version of
_exit
New submission from Abraham Karplus:
Exiting a Tkinter application normally results in printing '0' and exiting with
error code 1. This is a result of Tkinter's _exit function, whose default
argument for code is the string '0'. It then calls SystemExit with the code
argument. However
New submission from Abraham Karplus:
When a callback function gets called from Tkinter and raises SystemExit (either
directly or through sys.exit), a new SystemExit exception is raised with the
original exception as its code field, such as
SystemExit(SystemExit(),)
This is due to a bug
