void g_log_set_writer_func ( GLogWriterFunc func, gpointer user_data, GDestroyNotify user_data_free )
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
g_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.