Where is PostgreSQL software installed, and where are its data directory, configuration file, and log file?

The PostgreSQL install location is OS-specific:

Linux:

/usr/local/pfx/pgsql

Mac:

/Applications/pfx/pgsql

Windows (all versions):

C:\Program Files\pfx\pgsql

The data directory, configuration file, and log file are all located relative to the PostgreSQL install folder, <PGSQL_DIR>:

data: <PGSQL_DIR>/data

conf: < PGSQL_DIR>/data/postgresql.conf

log: < PGSQL_DIR>/pgsql.log