$ 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