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IBM OS/2 4.0 "Merlin" beta

La prossima release di OS/2 per piattaforma Intel. IBM ha deciso di andare avanti con il progetto OS/2, confortata dai lusinghieri risultati di vendita della versione Warp, suddividendo i "moduli" in diverse direzioni: supporto per PowerPC, sviluppo del microkernel, aggiornamento per la piattaforma Intel. Di quest'ultima ci occupiamo a partire da quest'articolo. Molte sono le "previsioni" basate sui dati e informazioni in circolazione ultimamente su Internet e sapientemente centellinate da IBM stessa. Negli ultimi giorni antecedenti la distribuzione di Beta è stata mandata in giro una preview grafica del desktop di Merlin nei newsgroup più caldi come comp.os.os2.apps e comp.os.os2.beta, che, smentiti subito da IBM, si è poi rivelata essere solo uno "snapshot" di una presentazione tenuta dalla Casa al Comdex Fall '95 su alcuni possibili orientamenti futuri per la GUI. Per questo non ve la presentiamo (è comunque visibile alla URL ftp://hobbes.nmsu.edu/incoming/merlin.gif) , ma si evince comunque un grandissimo interesse verso la prossima release del sistema operativo di Big Blue, deputata a dare un colpo ben più forte delle semplici spallate attuali d OS/2 Warp contro Windows 95. In quest'articolo, particolarmente, riportiamo un testo tratto dalla homepage delle Highly Unofficial IBM OS/2 beta FAQ curate da Kris Kwilas, sulle più papabili caratteristiche che Merlin incorporerà, al più tardi verso la metà del 1996.


Merlin is at the very least the code-name for the next Intel release of the OS/2 Warp client. John Soyring has used "Merlin" in a posting on Compuserve, so the name is at least semi-official. It may or may or may not apply to the entire "common code" strategy for future OS/2 releases on multiple platforms. See the Other section for some additional speculation.

Very little solid information about Merlin has been released. Three screen shots of "the direction" IBM is heading with the Warp interface were shown at Comdex. According to John Soyring, there are no plans to make these screen shots available in the near future.

Current plans supposedly call for the release of Merlin sometime around mid-1996. If IBM conforms to past behavior, there will be a wide external beta sometime before then. An informed _guess_ would be not expect anything before March at the earliest. Comments from IBMers have been to not expect anything for at least a couple on months.

*Until IBM announces an external beta program, there is no way most people can finangle a beta copy. If you are a developer or a large account, ask your local IBM rep. If an external beta program is announced, you _will_ know about it if you monitor comp.os.os2.beta and comp.os.os2.announce.*

What will probably be in Merlin?

Well . . . something old, something new, something borrowed, and lots of Blue - Kris Kwilas


A "fix" for the Single Input Queue (see the FixPack info below) Some portion of this has surfaced in FixPack 16. The inclusion of the fix has been confirmed by IBMers and others. See below.

OpenDoc runtimes. This OpenDoc support may also give users the ability to embed OLE 2.0 objects in OS/2 applications that support OpenDoc. At the moment, it appears that companies and developers are pushing hard for the integration of OpenDoc.

Updated User Interface

Security hooks in the OS. It appears that Merlin will incorporate C2 security extensions. However, it _strongly_ appears that these will only be the hooks to allow third-party developers to C2-enable the OS. These Security Enabling Services (SES) have already been shipped by IBM for OS/2 2.11. To the best of my knowledge, they are not available in a shipping product for OS/2 Warp. There is at least one RedBook available from IBM that has some information about SES.

Improved networking support. The Desktop will be more network-aware. Making connections with other systems should also be streamlined and automated with a feature that may currently be known as AutoConnect. Expect to find more of the networking code integrated into the base OS. This probably means we will see FTP and Web sites visually represented as object links, like in the newer revisions of the WebExplorer and some third-party utilities. You probably would not be too far from the mark if you thought that some of the new IBM Netcomber tools would find their way into the base OS.

HPFS improvements. The rumor mill is going full time with these. Since HPFS would need to be rewritten to a portable model for OS/2 Warp Connect for the PowerPC, it stands to reason that we will see it on Intel in the near future. Rumored features include the elimination of the 2GB file limit, shorter CHKDSK times, and a dynamic cache.

Developer API Extensions. These have been known as DAX/DAPIE in the press. See below under the Lotus products and FixPack 12 for more information.

Improved Plug and Play support. IBM has demonstrated a PM resource manager, so this could be implemented in much the same way as under Windows 95. However, I do not know if this will mean you can just drop a card in and have it automatically configure itself and load drivers. All the IBM references I have seen about this _specifically_ have mentioned something along the lines of "plug and play adapters." To me, this means PCI, PCMCIA/PCCard, or new ISA PnP adapters, not the dynamic loading of dynamic loading and configuration of legacy adapters.

Enhanced multimedia functions

Improved installation routines. Some sort of "Upgrade Advisor" along the lines of the one included in IBM's Windows 95 Recovery Kit will probably make an appearence.

ObjectREXX. Have you ever created your own OO GUI applications? Ever wanted to? You will . . . [More to come on this topic.]

The BonusPak will be enhanced (with at least portions OpenDoc enabled) and some new "surprises" will be added.

Generally referred to as "TrapDoor." This feature is already present in some preloaded IBM machines. Basically, you unload OS/2, leaving only a stub in memory. Then, your DOS application (or possibly Windows 95) that refuses to work under OS/2 executes. When you are finished, OS/2 puts you where you left off. This feature appears to be dependent on all the drivers supporting the APM specification. That is why this appeared first on preloads, as the manufacturer has more control over the drivers. For non-APM compliant machines, expect to see this function emulated in some way. This could present a very viable alternative for anyone who must occasionally run a Win32 application that is not supported under OS/2.

Support for connecting to infra-red printers, notebooks, etc.

Merlin should also include a set of communications API functions along the lines of TAPI in Windows. With any luck, this will also mean IBM will define a common address book/contact manager as part of the OS. If everyone is _really_ lucky, this PIM would be the obvious choice of Lotus Organizer for OS/2. But, who knows? ;-)

It is likely that Lotus cc:Mail will replace UltiMail/2 Lite as the mail client. This is consistent with the intentions stated by IBM after their purchase of Lotus. A new revision of cc:Mail would include support for POP amd SMTP as well as cc:Mail Post Offices.

Expect to see a Notes 4 Client bundled with the base OS. It is a good bet that it will be at the minimum a full "Express" client with mail capabilities, but you may not be able to develop applications without a full license.

"PowerSOM" support. Someone mentioned that PowerSOM refers to SOM 3.01 and DSOM 2.01. Expect improved stability and better performance. No further information is currently available.

Support for the VFAT file system. No, I do not know what form this support will take. With any luck, HPFS aware applications will be able to utilize LFNs on VFAT drives.

Win32s support will be enhanced to at least the 1.25 level.

More and more messages are indicating that there CommonPoint (i.e. the Taligent object frameworks) will be a part of the base OS. I have no additional information about which frameworks will be included.

Merlin should include dual-processor SMP support out of the box. See the OS/2 Warp SMP section for additional information. So many sources have winked and hinted at this, that I have decided to promote it in the rankings.

What might be in Merlin?


Someone mentioned that the new book "IBM's Official OS/2 Warp Connect PowerPC Edition" says that ATM and TrueType fonts are supported for OS/2 applications. Some East Asian DBCS versions of OS/2 already have native OS/2 TrueType support, so this may not be as big a leap as it sounds.

For anyone who is interested, the PMMERGE.DLL file shipped with FixPack 16 contains a reference to TrueType that was not there in previous versions.

An explicit option for NUMLOCK settings. ;-)

There have been several reports that IBM is working on Real Time extensions to OS/2. While these extensions may not become a part of the base OS, it is possible the the scheduling features of the Intel kernel will be enhanced.

As an aside, I saw one post where someone had seen a demonstration of some of this code at Comdex. Evidentally, there was some sort of gadget that was being used to balance a rod that was standing on its end. With the addition of the "Real Time Extensions," OS/2 was able to sense when the rod was about to tip over and alter the position of the base to keep it balanced. Sounds like a neat little project, but its applications outside of embedded systems will probably be limited at first.

There are rumors that Merlin will include a new file system. This may or may not be based on the Journaled File System (JFS) used on AIX machines. The JFS in AIX maintains a "journal" of what the file system will be doing in the future (i.e. pending write requests). After the write request is serviced, the journal is updated to reflect this. This allows the file system to recover from problems like OS crashes better. A second possibility for a "new" file system would be a journaled file system based on HPFS386. A third possibility is some kind of implementation of the Andrew File System (AFS).

Still a fourth possibility would be some kind of OO file system. There have been hints, but no one is talking.

David Charlap was kind enough to send me a brief overview of journaled file systems and AFS.

"I'm not too familiar with JFS, per se, but I do know a bit about how journaled file systems in general work.

The idea is that you have a reserve piece of the partition where the journal file resides. Whenever the disk is idle, the head sits over the journal space, over the track where the next data block will be written. (Which means there's probably a single journal partition that's used by all journalled file systems on the drive.) When writes are requested, the happen immediately to the journal file. This can happen amazingly fast because there should be no head movement involved. After this is done, the file system will then do the actual writeing and clean up the journal file. (This will happen during idle time, if possible.)

The idea is that if something catastrophic (like a power outage) happens, recovery will be nearly immediate. All to-be-written data (a-la lazy writes) will be somewhere in the journal file. So the CHKDSK program has only to read the journal file, and apply the journalled changes to the rest of the disk. It shouldn't be necessary to actually check out the entire file system.

As for the Andrew file system, Andrew is a project out of CMU for a distributed file system. It's sometimes known as AFS.

Like NFS, AFS creates a huge virtual file system, where you may have drives from all over your network mounted in the same place.

Unlike NFS, AFS is designed for wide area. You could have literally thousands of drives all over the world mounted together. Files and file systems can be moved around and the client apps will never know the difference.

AFS doesn't suffer from horrible performance bottlenecks by keeping a huge cache on your local hard drive. So after the first access to a file, you no longer need network access to continue accessing it.

AFS has other mechanisms for distributed file/record locking, update consistency, and other stuff."

What will not be in Merlin?


X - The IBM Microkernel. Merlin is based on the current OS/2 Warp kernel. While this may very well be the last version of OS/2 tied specifically to the Intel platform, as of this point in time Merlin is Intel specific. Expect to see a revision of OS/2 Warp Connect for the PowerPC shortly after the release of Merlin that updates the PPC UI, etc.

X - Support for Win32 binaries. IBM has stated that they will not be supporting Win32 binaries unless customer demand warrants it. In the meantime, developers can utilize the DAPIE extensions to maintain a high degree of code commonality that will allow them to easily recompile for Win32 or OS/2.

X - Support for Macintosh applications. Merlin will not support Macintosh applications.

As an interesting little aside, I keep receiving indications that a great deal of Merlin is being developed on the PowerPC. It will then be brought back to the Intel side of the house. Before anyone asks, this is in addition to the article that was printed on this after Comdex. At least three people who "seem" to know have commented that many of the Intel Merlin features exist or are being developed on the PowerPC version.


Copyright © 1995 Kris Kwilas.

Copyright © 1996 Beta Working Group. Tutti i diritti riservati.


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