set_writer_func

Set a writer function which will be called to format and write out each log message.

Each program should set a writer function, or the default writer ([func@GLib.log_writer_default]) will be used.

Libraries **must not** call this function — only programs are allowed to install a writer function, as there must be a single, central point where log messages are formatted and outputted.

There can only be one writer function. It is an error to set more than one.

Parameters:

func	log writer function, which must not be `NULL`
user_data	user data to pass to func
user_data_free	function to free user_data once it’s finished with, if non-`NULL`