FREEZE redirects updates to the database. Use FREEZE to coordinate database activity with the invocation of an operating system utility that accesses the database file.

To ensure that a copy or reorganized version of a database file contains a consistent set of records, concurrent MUPIP utilities, such as BACKUP (without the ONLINE qualifier) and EXTRACT, include mechanisms to ensure that the database does not change while the MUPIP utility is performing an action. Fidelity recommends the use of the -ONLINE qualifier with BACKUP.

If you want to use a non-GT.M utility to perform a backup or reorganization, you may give that utility stand-alone access to the file.

Common uses of the FREEZE command are:

The format of the FREEZE command is:

       
       F[REEZE] -OFF|-ON [-qualifier...] region-list
       

The region-list identifies the target of the FREEZE.

FREEZE must include one of the qualifiers:

The optional qualifiers are:

-OF[F]

Stops a ongoing FREEZE, unless used with -OVERRIDE. -OFF must be issued by the process that initiated the FREEZE. The -OFF qualifier is incompatible with the -ON and -RECORD qualifiers.

-ON

Specifies the start of a FREEZE. The -ON qualifier is incompatible with the -OFF and -OVERRIDE qualifiers.

-OV[ERRIDE]

Enables another process to end a freeze. -OVERRIDE should not be necessary (and may even be dangerous) in most schemes. -OVERRIDE is provided to allow error recovery in case a procedure with a freeze fails to release. The -OVERRIDE qualifier is incompatible with the -ON and -RECORD qualifiers.

-R[ECORD]

Specifies that the FREEZE utility should record an event as a reference point for subsequent backups. When a FREEZE specifies -RECORD, the current transaction identifier replaces the previously RECORDed transaction identifier for the database file. -RECORD is useful for integrating MUPIP BACKUP -BYTESTREAM with an external backup mechanism. The -RECORD qualifier is incompatible with the -OFF and -OVERRIDE qualifiers.