The C language itself operates at a level that is just high enough to be portable to variety of computer hardware. A great deal of publicly available Unix software is distributed as C programs that must be complied before use. Many Unix programs follow C's syntax. Unix system calls are regarded as C functions. What this means for Unix system administrators is that an understanding of C can make Unix easier to understand.
Why Use Unix? One of the biggest reasons for using Unix is networking capability. With other operating systems, additional software must be purchased for networking. With Unix, networking capability is simply part of the operating system. Unix is ideal for such things as world wide e-mail and connecting to the Internet. Unix was founded on what could be called a "small is good" philosophy. Not only was the hardware needed to run Unix too expensive to be within an individual's reach, but nobody imagined that would change in the foreseeable future.
So Unix machines were only available by the grace of big organizations with big budgets: corporations, universities, government agencies. But use of these minicomputers was less regulated than the even-bigger mainframes, and Unix development rapidly took on a countercultural air.
It was the early s; the pioneering Unix programmers were shaggy hippies and hippie-wannabes. They delighted in playing with an operating system that not only offered them fascinating challenges at the leading edge of computer science, but also subverted all the technical assumptions and business practices that went with Big Computing. Card punches, COBOL, business suits, and batch IBM mainframes were the despised old wave; Unix hackers reveled in the sense that they were simultaneously building the future and flipping a finger at the system.
At Purdue University, the Electrical Engineering Department made major improvements in performance, producing a version of UNIX that supported a larger number of users.
Purdue also developed one of the first UNIX computer networks. At the University of California at Berkeley, students developed a new shell and dozens of smaller utilities. By the late s, when Bell Labs released Version 7 UNIX, it was clear that the system solved the computing problems of many departments, and that it incorporated many of the ideas that had arisen in universities. The end result was a strengthened system.
The first Unix of which it can be said that essentially all of it would be recognizable to a modern Unix programmer was the Version 7 release in By this time Unix was in use for operations support all through the Bell System [ Hauben ], and had spread to universities as far away as Australia, where John Lions's notes [ Lions ] on the Version 6 source code became the first serious documentation of the Unix kernel internals.
Many senior Unix hackers still treasure a copy. The Lions book was a samizdat publishing sensation. Because of copyright infringement or some such it couldn't be published in the U. I still have my copy, which was at least 6th generation. Back then you couldn't be a kernel hacker without a Lions. The beginnings of a Unix industry were coalescing as well. But Microsoft's affection for Unix as a product was not to last very long though Unix would continue to be used for most internal development work at the company until after The Berkeley campus of the University of California emerged early as the single most important academic hot-spot in Unix development.
Unix research had begun there in , and was given a substantial impetus when Ken Thompson taught at the University during a sabbatical. By Berkeley was the hub of a sub-network of universities actively contributing to their variant of Unix. Ideas and code from Berkeley Unix including the vi 1 editor were feeding back from Berkeley to Bell Labs.
Berkeley's Computer Science Research Group was in the right place at the right time with the strongest development tools; the result became arguably the most critical turning point in Unix's history since its invention.
Early experiments with Ethernet were unsatisfactory. No FTP, no telnet, only the most restricted remote job execution, and painfully slow links.
Over the next decade, leveraging code he didn't write made Bill Gates a multibillionaire, and business tactics even sharper than the original deal gained Microsoft a monopoly lock on desktop computing. It was not apparent at the time how successful or how destructive Microsoft was going to be. There were things that seemed much more interesting going on — like the launching of Sun Microsystems.
They combined hardware designed at Stanford with the Unix developed at Berkeley to produce a smashing success, and founded the workstation industry. At the time, nobody much minded watching source-code access to one branch of the Unix tree gradually dry up as Sun began to behave less like a freewheeling startup and more like a conventional firm.
Berkeley was still distributing BSD with source code. It would only take about five years for C to drive machine assemblers almost completely out of use. There was still no port of Unix in either the System V or BSD versions; both groups considered the microprocessor woefully underpowered and wouldn't go near it. None of the Unix-workalikes were significant as commercial successes, but they indicated a significant demand for Unix on cheap hardware that the major vendors were not supplying.
Sun was already a success with imitators! Most Unix boosters thought that the divestiture was great news. What none of us realized at the time was that the productization of Unix would destroy the free exchanges of source code that had nurtured so much of the system's early vitality. Bootleg Unix tapes became far less interesting in the knowledge that the threat of lawsuit might come with them. Contributions from universities began to dry up. To make matters worse, the big new players in the Unix market promptly committed major strategic blunders.
One was to seek advantage by product differentiation — a tactic which resulted in the interfaces of different Unixes diverging. This threw away cross-platform compatibility and fragmented the Unix market.
The other, subtler error was to behave as if personal computers and Microsoft were irrelevant to Unix's prospects. Sun Microsystems failed to see that commoditized PCs would inevitably become an attack on its workstation market from below. A dozen small companies formed to support Unix on PCs; all were underfunded, focused on selling to developers and engineers, and never aimed at the business and home market that Microsoft was targeting. In fact, for years after divestiture the Unix community was preoccupied with the first phase of the Unix wars — an internal dispute, the rivalry between System V Unix and BSD Unix.
The dispute had several levels, some technical sockets vs. System V termio and some cultural. Thus we fiddled while Rome burned. The patch program, a simple tool that applies changebars generated by diff 1 to a base file, meant that Unix developers could cooperate by passing around patch sets — incremental changes to code — rather than entire code files. This was important not only because patches are less bulky than full files, but because patches would often apply cleanly even if much of the base file had changed since the patch-sender fetched his copy.
With this tool, streams of development on a common source-code base could diverge, run in parallel, and re-converge. The patch program did more than any other single tool to enable collaborative development over the Internet — a method that would revitalize Unix after In Intel shipped the first chip, capable of addressing 4 gigabytes of memory with a flat address space.
The clumsy segment addressing of the and became immediately obsolete. This was big news, because it meant that for the first time, a microprocessor in the dominant Intel family had the capability to run Unix without painful compromises. The handwriting was on the wall for Sun and the other workstation makers.
They failed to see it. Very few people took him or his GNU project seriously, a judgment that turned out to be seriously mistaken. Ritchie rewrote B and called the new language the C language. The third edition of Unix was released in February The fourth edition of Unix was released in November The fifth edition of Unix was released in June Frustrated with ed , Joy developed a more featured editor em.
The sixth edition of Unix was released in May Bourne shell was introduced begins being added onto. The seventh edition of Unix was released in January The eighth edition of Unix was released in February Dobb's Journal.
The GNU project starts a year and a half later. The ninth edition of Unix was released in September
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