Reduce the time to know trigger_fi​le's existence

Hi,

We are trying to introduce a thread that monitors the creation of the
trigger_file. As and when the file is created, the process that monitors
postgres server needs to be notified through the inotify API.

This is to reduce the 3-4 seconds delay that exists with the current
implementation in postgres. As per the current implementation, the thread
checks for the existence of the file every 5 seconds. If the file got
created just 1 second after the sleep, there is a wait time of 4 seconds
before we know whether the file is present or not. We intend to avoid this
delay by using inotify().

PostgreSQL version number you are running: postgres 9.1.5

How you installed PostgreSQL: Downloaded and compiled the sources

Does anyone have suggestions on the appropriate place to
add inotify_add_watch to achieve our objective?
Thanks in advance.