Dmitry Markman <dmarkman(at)mac(dot)com> writes:
> suppose I started the server with the following command
> pg_ctl -D . . . start -l <logfilename>
> is there a way to get <logfilename> later by sending some query to the server or
No, the server has no way to know where its stdout/stderr were
pointed to. You might want to enable the syslogger output method
(see logging_collector) to have something a bit more featureful.
https://www.postgresql.org/docs/current/runtime-config-logging.html
regards, tom lane