Separating config using PGDATA does not seem to behave as described in the docs about postgres HOT 12 OPEN

$ ls -lan data/
total 8
drwx------ 2 1000 1000 4096 May 13 15:28 .
drwxrwsr-x 6 1000 1000 4096 May 13 15:15 ..
$ ls -ln conf/postgresql.conf
-rw-r--r-- 1 1000 1000 68 May 13 15:52 conf/postgresql.conf
$ cat conf/postgresql.conf
data_directory = '/var/lib/postgresql/data22'
shared_buffers=2048MB
$ docker run -it --rm -e POSTGRES_PASSWORD=foo \
  -v "$PWD/data:/var/lib/postgresql/data22" \
  -v "$PWD/conf/:/etc/postgresql/" \
  postgres:15 -c config_file=/etc/postgresql/postgresql.conf
...
fixing permissions on existing directory /var/lib/postgresql/data ... ok
...
2024-05-13 22:53:33.200 GMT [43] LOG:  skipping missing configuration file "/var/lib/postgresql/data22/postgresql.auto.conf"
waiting for server to start....2024-05-13 22:53:33.211 GMT [48] LOG:  skipping missing configuration file "/var/lib/postgresql/data22/postgresql.auto.conf"
2024-05-13 22:53:33.211 GMT [48] FATAL:  data directory "/var/lib/postgresql/data22" has wrong ownership
2024-05-13 22:53:33.211 GMT [48] HINT:  The server must be started by the user that owns the data directory.
 stopped waiting
pg_ctl: could not start server

$ ls -lan data/
total 8
drwx------ 2 1000 1000 4096 May 13 15:28 .
drwxrwsr-x 6 1000 1000 4096 May 13 15:15 ..

initdb: error: directory "/etc/postgresql" exists but is not empty

sudo docker run -e POSTGRES_PASSWORD=foo -v /example/postgresql.conf:/etc/postgresql/postgresql.conf -v /example/postgresql-data:/var/lib/postgresql/data postgres:15.2 -c config_file=/etc/postgresql/postgresql.conf

$ sudo grep data_directory /example/postgresql.conf
data_directory = '/var/lib/postgresql/data'             # use data in another directory

initdb: error: directory "/etc/postgresql" exists but is not empty
initdb: hint: If you want to create a new database system, either remove or empty the directory "/etc/postgresql" or run initdb with an argument other than "/etc/postgresql".

$ ll
total 32K
drwxr-x--- 2    999 root   6 May 13 23:48 data
-rw-r--r-- 1 tucked root 29K May 13 23:45 postgresql.conf
$ sudo ls -l data
total 0
$ grep data_directory postgresql.conf 
data_directory = '/data'                # use data in another directory
$ sudo docker run --name postgres -e POSTGRES_PASSWORD=foo -v $PWD/postgresql.conf:/etc/postgresql/postgresql.conf -v $PWD/data:/data postgres:15.2 -c config_file=/etc/postgresql/postgresql.conf
The files belonging to this database system will be owned by user "postgres".
This user must also own the server process.

The database cluster will be initialized with locale "en_US.utf8".
The default database encoding has accordingly been set to "UTF8".
The default text search configuration will be set to "english".

Data page checksums are disabled.

fixing permissions on existing directory /var/lib/postgresql/data ... ok
creating subdirectories ... ok
selecting dynamic shared memory implementation ... posix
selecting default max_connections ... 100
selecting default shared_buffers ... 128MB
selecting default time zone ... Etc/UTC
creating configuration files ... ok
running bootstrap script ... ok
performing post-bootstrap initialization ... ok
syncing data to disk ... ok


Success. You can now start the database server using:

    pg_ctl -D /var/lib/postgresql/data -l logfile start

initdb: warning: enabling "trust" authentication for local connections
initdb: hint: You can change this by editing pg_hba.conf or using the option -A, or --auth-local and --auth-host, the next time you run initdb.
2024-05-13 23:50:06.653 GMT [42] LOG:  skipping missing configuration file "/data/postgresql.auto.conf"
waiting for server to start....2024-05-13 23:50:06.701 GMT [47] LOG:  skipping missing configuration file "/data/postgresql.auto.conf"
2024-05-13 23:50:06.702 UTC [47] FATAL:  "/data" is not a valid data directory
2024-05-13 23:50:06.702 UTC [47] DETAIL:  File "/data/PG_VERSION" is missing.
 stopped waiting
pg_ctl: could not start server
Examine the log output.