Issue 1-30, July 3, 1996

Be Engineering Insights: The Secrets of Be Sockets

By Bradley Taylor

As many of you know, Be uses a variation of the Berkeley socket interface. Writing socket code on the BeBox has been something of a black art, since our documentation is only a single page! In this article, I hope to clear up some of the mysteries of Be socket programming. If you aren't already familiar with Berkeley sockets, then this article will be extremely boring for you. For the rest of you, this article will be merely boring.

The most important thing to remember when using Be sockets is that they're not file descriptors the way Berkeley sockets are. This difference is felt in a number of ways:

The next point has to do with unblocking a blocked socket call. In a single-threaded UNIX system, you can do this with a signal, which will cause the blocking call to unblock. This currently doesn't work under the Be OS, and signals aren't really a very good way of doing this in a multithreaded system anyway. So the rule is that any blocked socket call can be unblocked simply by operating on that same socket in another thread.

For example, if a socket is blocked on recv(), it can be unblocked by another thread calling send() on the same socket. (If you don't actually want to DO anything, call something innocuous like getsockname().) Currently, an interrupted read returns a status of -1; in DR8, errno will be set to the more descriptive EINTR. This isn't much different from single-threaded UNIX, since in order to operate on the same socket when you're blocked, you must do so in a signal handler that will cause the blocked call to fail and set errno to EINTR.

(For any of you who might be wondering about the thread safety of setting the errno variable, you can relax: In DR8, errno is *not* a global variable. Through the magic of the C preprocessor and function calls, errno returns a value that is unique per thread.)

A Be OS socket blocks if there isn't any data to be read, and unblocks when data arrives. This is precisely the UNIX behavior, as far as it goes, but UNIX also lets you specify nonblocking I/O as an option. This option will be available in DR8: In nonblocking mode, a socket that would otherwise have blocked will, instead, immediately return EWOULDBLOCK (this is the same as System V's EAGAIN).

Another item worth mentioning is select(). Under UNIX, you can put any descriptor into the select mask. Typically, the mask only contains two sockets, but sometimes tty descriptors are thrown in there, as well. The Be OS only supports sockets in the select mask. Also, it only reports descriptors that are blocked on read. The write mask always reports that sockets are ready for writing, even if they may block. (This is something that will probably be fixed in DR8.)

I recommend avoiding select() if you can, because it isn't really the right way to do socket programming in a multithreaded system. It's implemented by spawning a lot of threads that block, and so it isn't any more efficient than spawning the threads yourself. You should spawn threads for blocking calls, and use the trick described above (operating on the same socket in another thread) if you need to unblock any of the threads.

The next point concerns the netdb functions (gethostbyname(), getservbyname(), and so on). The only netdb functions that are completely implemented right now are the host lookup functions, gethostbyname() and gethostbyaddr(). The others, such as getservbyname() and getprotobyname(), are minimally implemented now, but will likely be fully implemented in a future release.

Most of the options that you can set with setsockopt() are not implemented. Again, these will get implemented in future releases.

An infelicity that will likely be cleared up in DR8 concerns server TCP code that binds to the address "". In UNIX, this is understood to mean "bind to all interfaces." In DR7 of the Be OS, it means "bind to the first interface you find." Typically, the interface that's found first is your Ethernet or PPP interface; your server will NOT bind to the local loopback address of "". If you need local clients to talk to the server, then you need to explicitly bind to the address "" with another socket. Thus, your server is actually listening on two sockets: One for the external network and one for the internal loopback network.

In summary, the basic stuff is implemented and many people have been successful writing network code on the BeBox. If you're porting code, you may have some trouble with some of the more obscure stuff that isn't implemented yet, or with the fact that Be sockets aren't file descriptors. This should be cleared up in future releases, although making Be sockets real file descriptors is probably a long way off.

Be Developer Profile: Paul Popernack

By Paul Popernack

I remember the fateful day last fall when I typed "" into my Web browser and was treated to a vision of the future of personal computing. What I saw and read was breathtaking. I picked my jaw back up off the floor, wiped the drool off my keyboard, and went back for a second look. Could it be true? A dual-processor machine, tons of I/O, a modern OS complete with multiprocessing, multithreading, memory protection, and an integrated database—all at an affordable price?

The BeBox was the first computer that made me want to give up my Macintosh. Coming from a Mac-fanatic like me, that's a pretty serious statement.

I've been working on the Macintosh since 1987, when I co- developed a HyperCard database program for an archaeology research project at the University of Maryland. After getting my anthropology degree in 1991, I plunged straight into—you guessed it—the computer field. What's an anthropologist doing in computers? I'll let you do the math...

In the last five years, I've developed and maintained numerous research databases for a military medical project, using mostly Macintosh computers with statistical analysis done on a VAX. Whereas I started out doing mostly database development, I've expanded my scope to the much more exciting world of multimedia development. My current position focuses almost entirely on multimedia and program development with a special emphasis on medical and emergency medical readiness.

But I digress. Back to me finding Be on the Web... The BeBox and Be OS looked like hot stuff—too good to keep to myself—so I walked down the hall to a friend's office (he's an NT guy) and said, "Point your browser at and check this out."

"Hmmm...interesting...seems a bit like the NeXT though..." he said.

The low price tag and use of the PC-clone organ bank made him take a second look, but it was when I showed him the Be demo video that he became a Be-liever. There's nothing like seeing the BeBox in action to turn skeptics into Be-lievers.

The BeBox presents a unique opportunity for a fresh start. It offers a clean, open highway to the next generation in personal computing—and that's where I want to be: Contributing to the growth of a new OS. It's exciting! The glowing comments in from Peter Lewis and John Norstad—two Macintosh developers for whom I have the highest regard -- really caught my attention. If THESE guys are hot on the BeBox...

Not only are the BeBox and Be OS pretty special, but so are the people behind Be. Developer support is exquisite, in fact, I'd say it's the best I've ever encountered. Be seems to understand that happy developers are key to their success.

Currently I develop for the BeBox on my own time, although my employer is expressing a growing interest in the platform. Right now I'm working on a text editor and some desktop utility programs to sink my teeth into the Be OS. I'm particularly excited about the BMessaging capability and having applications talk to each other and work together. That's the anthropologist in me.

I'm also interested in supporting a Be Users' Group in the Washington, DC, area. If you're in the DC area and would like to get together, please e-mail me at

My beret goes off to JLG and the folks at Be. You all have created something very special. I can't wait to reciprocate.

Be Marketing Mutterings

By Alex Osadzinski

If you've been reading Be newsletters for a while, it will come as no surprise that our primary focus is on developers. Today, we only sell machines to bona fide developers who are enrolled in our developer program, and we devote all of our sales and marketing efforts to recruiting and supporting new developers. However, we get many enquiries from end users, resellers, VARs, and other nondevelopers who want to buy or resell BeBoxes. So, what are our plans?

By the late fall of this year, we expect tens, and then hundreds, of interesting new applications to ship on the Be OS and BeBox. For our sake, and the sake of our developers, we need to have ways to get product to the end users of these applications and, just as important, ways to provide hardware and software support. To this end, our intention is to offer direct mail/web order sales from Be, with Internet- based support, and to work with qualified resellers who will be able to configure, sell, service, and support products in specific geographic or application markets. Market efficiencies will guarantee that direct and reseller pricing will be very close, so the end user will have a true choice of how and where to buy BeBoxes. A partnership between Be, application developers, and resellers will be able to deliver solutions to end users; there's nothing innovative about this idea, but it has the great advantage that it's known to work well and to create satisfied customers. The most innovative aspect will be the cost (and hence price) reductions that will come from Internet-based software distribution and support services.

There's a class of end user who doesn't want to wait for applications. These are the true geeks (and we use that term with affection, as many of us at Be could easily be described as geeks), who don't necessarily want to develop applications for others but who want a neat platform to experiment with. The only reason that we're not offering BeBoxes to this geek market right now is that we're awaiting FCC Class B approval. We expect to be able to offer BeBoxes to the geek/hobbyist market in August; we'll announce it on our Web page and in this newsletter when the time comes.

We're very enthusiastic about working with the geek market: It's populated with fearless, creative, and innovative individuals who will torture our product and its new applications and figure out ways to use it that we couldn't begin to imagine.

US Uber Alles—The Opportunity

By Jean-Louis Gassée

Fifteen years ago the conventional wisdom was that the US computer industry was about to be streamrolled by the Japanese, in the same way they had flattened everything else on their path—from cameras to steel mills, from stereos to autos. They had the determination, the government support, the technology, and the discipline to conquer any market on which they set their sights.

In spite of these dire predictions, the US computer industry is doing very nicely. In some respects it's doing even better than fifteen years ago: It now virtually dominates Western Europe and has made substantial inroads in Japan. US domination is even more striking if we focus on software: Companies such as Microsoft, Oracle, Netscape, and Apple own the OS and application markets world-wide.

If this is the case—if only American software products can succeed -- why do we even bother to evangelize and support developers in Australia, Iceland, France, or Finland? Are we financing yet another remake of "Beau Geste," or do we know something the rest of the industry doesn't know? It's a trick question, which offers little real choice: Foolishness or arrogance. But the trick is well-known. It's hidden in the assumptions that are made about the software trade.

We're told that large US companies dominate the software market because of the huge development and marketing investments required to wage war. The linchpin of this argument is in its mixing of two notions: "US" and "large." We simply don't buy this line. Neither US-centricity nor a work force the size of a small town with a concomitant budget are necessary in the new software world.

Let's look at the size argument: Does good software require a long and expensive gestation and a cast of thousands? If you're an established player updating a legacy application, then yes, it does. That's because existing programming models have become unendurably baroque, and because established companies tend to be conservative: They dedicate most of their resources to conserving their franchise, their existing business, whether it's application software or an operating system. Individual authors and small companies have mixed feelings about entering and playing in the legacy markets; the ocean is wide, but inhabited by nasty predators that can devour small fish faster than these fish can spawn. A fresh developer in the office-automation market has to spend roughly the same amount of time sifting the arcana of a baggage-laden OS as the big guys, but must do so without the benefit of a large and well-paid squad of marketeers and spin artists defending the line and clearing some space on the shelf at Fry's.

Conversely, with the BeBox, one or two individuals can write a major application in a fraction of the time and cost that it would take on an older platform: The programming model is simpler, (still) free from baggage, and code size is correspondingly smaller (by a factor of four or five). As expected, baggage-free code is also faster code. Admittedly, developers could harbor a mix of sentiments towards the Be platform: Exciting and unencumbered, yet unproven. But once we add the Internet, the leap of faith becomes safer for a larger number of developers in a wider range of locations.

Some have called the Internet the new printing press. But it's also a great marketing and distribution equalizer. A software developer in Finland can promote and deliver an application as easily and quickly as a competitor in the heart of Silicon Valley. But is the spreadsheet from a company in San Jose, simply by the fact of the company's location, better than the one from Helsinki? If you look at the demographics of the US software industry, you begin to suspect that the last decade of US domination wasn't entirely home-grown: In a land of immigrants, the software industry is well-populated by programmers from other countries (our company, minuscule as it is, is no exception). In fact, the advantages of developing in the US are mostly historical and coincidental —it's no great surprise that young, well-paid programmers have, in the past, jumped at the chance to live in California.

But when programmers can't come to the US, we'll go to them, via the net. Size and location are no longer the issue. With exciting new technology, a platform unencumbered by large competitors, with inexpensive market access, the most important question is: "Who can write the best code?" It may not be the only question. But it is the first one—before company size and location.

BeDevTalk Summary

A number of heavy-traffic threads (notably "Call for type/creator reorganization") disappeared this week. The help system thread is still reasonably strong; "GUI/shell replacement" is losing steam. And to answer a question that was posed in one of this week's threads: Yes, Be does listen to the suggestions made in BeDevTalk.

More for amusement than anything else, the age of each thread ("NEW", "WEEK 2", and so on) is announced above the subject line. Older threads are given first.

Threads topics are given by the subject lines as they appear (literally, typos and all) in the mail. We don't summarize every thread, so don't take it personally if your favorite is left out. Better yet: Start a thread.

To subscribe to BeDevTalk, visit the mailing list page on our web site:

Subject: Suggestions for a Help system?

This thread has become an HTML battleground. In addition to the staunch pro and con views, there are also opinions regarding the invention of app-specific HTML tags.

We also learned that the perlism "$_" is pronounced "ding- under."

Subject: GUI/shell replacement

More thoughts on parting the iron curtain that separates shells from GUI windows. This week: Should the Browser provide a name-only mode when displaying items in the dock?

Subject: Virus Software

How should the BeBox protect the motherboard from a virus that's loaded into the EEPROM? Latched (once-per-boot) access to the EEPROM was suggested.

THE BE LINE: We're working on it.

Subject: Browser Add-ons

Where should the add-ons that apply to a particular Browser item be displayed? Currently, you have to right click and descend the "Add-ons" submenu. It was suggested that the add-ons should be in the item's top-level context menu. Should this decision (submenu versus top-level menu) be settable in a preference?

Subject: OpenDoc

A few participants lauded the concept of OpenDoc, and have suggested that some of the BeBox's "missing features" would be filled in by supporting ODF. The ensuing negative reaction was countered with a) a request for more descriptive evidence of ODF's flaws and b) the suggestion that designing something better is possible, but, given that OpenDoc exists today, spending the time to design the alternative may be a waste.

Subject: record_ref Persistence?

This thread started with questions: Are record_refs values maintained through a database reindex? (Yes.) Through a database rebuild? (No.)

It then moved into a larger discussion of what a record_ref actually identifies, whether you should use refs instead of names, what sort of user prefers symbolic (that is, ref- like) identification as opposed to filenames, how refs and filenames compare when fit into the live query world, whether refs are simply new-fangled gizmos that will never replace the reality of pathnames, and so on. A pleasantly heated discussion on a topic that is, after all, at the heart of one of the selling points of the Box.

Subject: Write a mailer!

Jon Watte (Metrowerks) outlined a command-line mail-sending program and opined that it would probably be a one-night hack to get the thing working. A five-minute (shell script) implementation showed up a few days later; also, news of a mail server was posted.

Woven throughout was a discussion of what Be's mail API should look like, and what mail services Be should provide. (A branching thread about add-ons is summarized below.)

THE BE LINE: Be will provide a mail daemon and mail API with DR8. Nothing terribly fancy—we're not out to compete with our developers —we just want to provide a base level of support for certain features in the SMTP/POP world.

Subject: Add-ons

Within this thread (sprouted from "Write a mailer!") were technical descriptions of how add-ons work, how to tell CodeWarrior to share data between add-ons, and so on, as well as a discussion of whether/where Be should allow a repository for "global" add-on modules, whether script-like manipulations (provided by an add-on) should be performed on an open document (as opposed to having to drop the document on an add-on icon), and to what extent Be should allow its interface to be customized through add-ons.

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