Description
pg_controldata prints information initialized during
initdb, such as the catalog version and server locale.
It also shows information about write-ahead logging and checkpoint
processing. This information is cluster-wide, and not specific to any one
database.
This utility may only be run by the user who initialized the cluster because
it requires read access to the data directory.
You can specify the data directory on the command line, or use
the environment variable PGDATA.