blocking pgsqlGetNotify

[Gemorroj]

Hi.
PDO have pgsqlGetNotify function with second parameter like sleep.
How to correct use that function?
I wrote some example code (sse server using listen/notify postgres functionality).
See at the line https://github.com/Gemorroj/swoole-sse/blob/main/server.php#L40, is it correct? or i need wrap it to corutine or smething else?