Introduction

UpdateMaker 2 is an application that can determine the differences between any two or more Macintosh files, be they applications, documents, system files, or whatever. 

UpdateMaker documents describe the changes needed to convert one or more files (called the “old” files, whether they are older or not) into the “new” file. You cannot read UpdateMaker documents, since they are stored in a compact form. However, you can apply the UpdateMaker document to any one of the “old” files and it will generate an exact copy of the “new” file.

Why is this useful? Because UpdateMaker documents can be very much smaller than the files that they apply to, they cost less to send over a computer network or store on a disk. If you wish to send some changes to a large document or a large application to someone who has an older version, sending an UpdateMaker document will cost less than sending the entire document or application. UpdateMaker documents are also more secure in that they can only be used by someone who has one of the “old” files. UpdateMaker’s ability to combine updates for several alternative “old” files into one document is useful when making one update for multiple users who have different versions of the “old” file.

Because not everyone who might want to update a file will have a copy of UpdateMaker to apply UpdateMaker documents with, UpdateMaker can also save documents as stand-alone applications. These applications are good for one and only one job – updating the particular files that they were created for. But they can be convenient if you do not know that a copy of UpdateMaker will be available to the receiver of the UpdateMaker document. The stand-alone applications, like UpdateMaker itself , require System 6 or later.

UpdateMaker documents and stand–alone applications are inherently reliable. They have internal checks that will detect damage done to them in transit. They also check that those parts of the target file that they copy or modify are identical to those in the author’s old files. The final file is therefore guaranteed to be an exact copy of the author’s new file, subject only to any special exceptions specified by the author of the update.