Old FrameMaker versions

[Syed Zaeem Hosain (Syed.Hosain@aeris.net)]

> And the situation is more complex again on Mac, where the file type byte is retained in some files for backward compatibility with pre-OS X OS versions, which built an invisible database that matched files with their home application, but OS X (Unix under the covers) also takes a file name extent into consideration. (And on OS X you can have up to half a dozen apps that can open, say, a PDF.)

Hmmm .... I would have thought (but not certain) that the current OS X release did not use the file name extension to select the app for opening PDF files. It _probably_ looks at the magic bytes just like other UNIX systems.

Which, in the case of PDF files, would be the leading bytes "%PDF-" inside the files.

A question though: if you have more than one app available to open a PDF file, how does OS X actually select which app to use?

In Windows, there is one default for each extension, but you can override that with a right-mouse-click on the file in Explorer, followed by a "Open With ..." and then select/specify the app.

Z