Gdb Default Window Configuration File

In Emacs 29 it is possible to define a Gdb Default Window Configuration File to customize the window layout of gdb many windows. ​ How does such a file has to look like? I cannot find any example anywhere

Yes, see here: https://www.gnu.org/software/emacs/manual/html_node/emacs/GDB-User-Interface-Layout.html

It's already in Emacs 28. Just activate `gdb-many-windows` in a gdb section. Change the layout as you like (divide windows, etc), then call `gdb-save-window-configuration` to save the configuration to a file. You can load it with `gdb-load-window-configuration`. The `gdb-default-window-configuration-file` variable is just a way to load a configuration file on startup.

Thanks. And the save command should be invoked with a gdb hook?