pg_ctl reload query

Hi All,

Wanted to know what does pg_ctl do in the background when we run *pg_ctl
-D datadir reload *

After modifying the entries in pg_hba.conf file we ran the reload
command. Generally, it just reloads the files and everything works fine.
But strangely, last time when we ran the reload command and tried to
access *psql dbname, *
It gives a message *"database shutting down" *

As far as i know, this msg appears only when a restart command is given.

Please let me know if my understanding is right and what could have gone
wrong for the db to shutdown.

Thanks and Regards,
Shilpa

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