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Chapter 4 - Alias Manager / Using the Alias Manager

Customizing Alias Records

An alias record contains two kinds of information: public information available to your application and private information available only to the Alias Manager. Your application can use the first field, userType, to store its own signature or any other data that fits into 4 bytes. Your application can use the second field, aliasSize, to customize the alias record for storing additional data.

The Alias Manager stores, in the aliasSize field, the size of the record at the time it is created or updated. To customize an alias record, you first use the Memory Manager's SetHandleSize procedure to increase the size of the record. You can then find the starting address of your own data in the record by adding the record's starting address to the length recorded in the aliasSize field. If you use the Memory Manager to expand the record, the Alias Manager preserves your data, even if it changes the size of its own data when updating the record.

Note

In general, you should customize only alias records that you
have created.