Juda$ wrote:6.5.26f any idea what the "f" means ?
It means "Feature" release stream, as opposed to "Maintenance" release stream.
Maintenance releases contained "bug fixes, performance enhancements including new hardware platform support, and standards-based changes."
Feature releases contained major new software packages that were not included in previous versions of IRIX and various optional features. Feature releases contained all of the components of Maintenance releases.
During an initial installation of IRIX, the installer program asks the user to select a release stream. Once a stream is selected, all subsequent updates will use stream-specific options. While it is possible to switch streams after the initial IRIX installation, it can be a tedious process.
The content of the Feature stream was added to the Maintenance stream as of IRIX 6.5.22, making the concept of different release streams irrelevant. Basically, as of IRIX 6.5.22, all versions of IRIX are on the same stream, whether they report themselves as "m" or "f".
For your version, 6.5.26, the "f" is there for historic/compatibility reasons and has no practical meaning.