$ pg_controldata /var/lib/postgresql/data
pg_control version number: 74
Catalog version number: 200411041
Database system identifier: 4938897450188078907
Database cluster state: in production
pg_control last modified: Sat Sep 2 03:35:50 2006
Current log file ID: 0
Next log file segment: 29
Latest checkpoint location: 0/1C000490
Prior checkpoint location: 0/1C000454
Latest checkpoint's REDO location: 0/1C000490
Latest checkpoint's UNDO location: 0/0
Latest checkpoint's TimeLineID: 1
Latest checkpoint's NextXID: 22669950
Latest checkpoint's NextOID: 846684
Time of latest checkpoint: Sat Sep 2 03:35:00 2006
Database block size: 8192
Blocks per segment of large relation: 131072
Bytes per WAL segment: 16777216
Maximum length of identifiers: 64
Maximum number of function arguments: 32
Date/time type storage: floating-point numbers
Maximum length of locale name: 128
LC_COLLATE: C
LC_CTYPE: C
$ pg_controldata /var/lib/postgresql/data.bu/
pg_control version number: 74
Catalog version number: 200411041
Database system identifier: 4938897450188078907
Database cluster state: shutting down
pg_control last modified: Sat Sep 2 01:53:17 2006
Current log file ID: 0
Next log file segment: 27
Latest checkpoint location: 0/1A85D9C8
Prior checkpoint location: 0/1A85D98C
Latest checkpoint's REDO location: 0/1A85D9C8
Latest checkpoint's UNDO location: 0/0
Latest checkpoint's TimeLineID: 1
Latest checkpoint's NextXID: 22669921
Latest checkpoint's NextOID: 846684
Time of latest checkpoint: Mon Aug 7 16:27:40 2006
Database block size: 8192
Blocks per segment of large relation: 131072
Bytes per WAL segment: 16777216
Maximum length of identifiers: 64
Maximum number of function arguments: 32
Date/time type storage: floating-point numbers
Maximum length of locale name: 128
LC_COLLATE: C
LC_CTYPE: C