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discovered that several issues are still prevailing, while others were resolved. Raymond concludes that not all concepts behind Unix can be deemed as non-functional even though the book's intention may have been to portray Unix as inferior without encouraging discussions with developers to actually
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Unix systems are preemptively multitasking: multiple processes can run at the same time, or within small time slices and nearly at the same time, and any process can be interrupted and moved out of execution by the kernel. This is known as
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covers some of these design features as failures from the user point of view. However, although some information is quite dated and cannot be applied to modern Unixes or Unix-like operating systems such as
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With few exceptions, devices and some types of communications between processes are managed and visible as files or pseudo-files within the file system hierarchy. This is known as
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standard. No single published standard describes all Unix architecture computer operating systems — this is in part a legacy of the
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The UNIX operating system supports the following features and capabilities:
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and trap handling, separation between user and system space,
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The kernel provides these and other basic services:
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41:Please help
36:verification
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920:MKS Toolkit
731:OpenSolaris
288:management.
221:Concurrency
195:Unix kernel
158:Description
1015:Categories
941:PWS/VSE-AF
838:SerenityOS
745:Tru64 UNIX
720:OpenServer
472:Philosophy
462:Filesystem
364:References
255:scheduling
203:scheduling
69:newspapers
776:Domain/OS
492:Operating
439:Unix-like
329:Criticism
247:interrupt
183:Unix-like
164:Unix-like
152:Unix wars
99:July 2008
987:Category
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770:Coherent
752:UnixWare
686:System V
639:ChromeOS
594:NeXTSTEP
579:bridgeOS
477:Security
352:See also
265:Features
999:Commons
977:Italics
906:MachTen
899:Interix
879:Darling
850:more...
737:Illumos
725:Solaris
659:Red Hat
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574:watchOS
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532:OpenBSD
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494:systems
467:History
83:scholar
885:Eunice
874:Cygwin
866:layers
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145:POSIX
90:JSTOR
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786:Hurd
714:IRIX
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664:SUSE
634:Arch
569:tvOS
444:and
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148:IEEE
124:Unix
62:news
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45:by
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