Dynamically allocating the ACB staging library for ACBLIB member online change

Use the DFSMDA member with TYPE=IMSACB to dynamically allocate the ACBLIB staging library for use with ACBLIB member online change.

You can dynamically allocate the ACBLIB staging library using the DFSMDA member TYPE=IMSACB. By using TYPE=IMSACB, you only have to specify the data set name for the staging ACBLIB. A dynamic allocation member with the name of IMSACB is created for the staging ACBLIB.

Restriction: The staging ACBLIB cannot be concatenated.

Restriction: Do not create database MDA members with a DDNAME=IMSACB or with DISP=OLD.

IMS dynamically allocates the staging ACBLIB with DISP=SHR.

To ensure that the staging ACBLIB can be allocated by your IMS control region, you can use either of the following methods:

Create a DFSMDA member for ACBLIB staging library. For example:

DFSMDA TYPE=INITIAL
DFSMDA TYPE=IMSACB,DSNAME=STAGING.LIBRARY
DFSMDA TYPE=FINAL

Add an IMSACB DD statement to your IMS procedure. For example:
```
//IMSACB DD DSN=STAGING.LIBRARY,DISP=SHR
```
If you use the IMSACB DD statement, it takes precedence over the DFSMDA member settings.