How can I make a plugin “save a new file”?

I’m a beginner, and I want my plugin’s UI button to export a CSV file and write content into it when clicked.
But from what I see, the official SDK doesn’t seem to provide similar examples, and I have no idea how to implement this.
It’s like in AE scripting with .saveDlg() → .open() → .write() → .close().
I’d like to see an example if possible.

static PF_Err ParamsSetup(PF_InData* in_data, PF_OutData* out_data, PF_ParamDef* params[], PF_LayerDef* output) {
	PF_ParamDef	def;

	......
	AEFX_CLR_STRUCT(def);
	PF_ADD_BUTTON("TTT", "ttt", NULL, NULL, ID_BUTTON);

	......
	out_data->num_params = ID_NUM_PARAMS;

	return PF_Err_NONE;
}