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Version 3 Unix
The term "Research Unix" refers to early versions of the Unix operating system for DEC PDP-7, PDP-11, VAX and Interdata 7/32 and 8/32 computers, developed in the Bell Labs Computing Sciences Research Center (CSRC). History The term ''Research Unix'' first appeared in the Bell System Technical Journal (Vol. 57, No. 6, Pt. 2 Jul/Aug 1978) to distinguish it from other versions internal to Bell Labs (such as PWB/UNIX and MERT) whose code-base had diverged from the primary CSRC version. However, that term was little-used until Version 8 Unix, but has been retroactively applied to earlier versions as well. Prior to V8, the operating system was most commonly called simply UNIX (in caps) or the UNIX Time-Sharing System. AT&T licensed Version 5 to educational institutions, and Version 6 also to commercial sites. Schools paid $200 and others $20,000, discouraging most commercial use, but Version 6 was the most widely used version into the 1980s. Research Unix versions are often ref ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Unix
Unix (; trademarked as UNIX) is a family of multitasking, multiuser computer operating systems that derive from the original AT&T Unix, whose development started in 1969 at the Bell Labs research center by Ken Thompson, Dennis Ritchie, and others. Initially intended for use inside the Bell System, AT&T licensed Unix to outside parties in the late 1970s, leading to a variety of both academic and commercial Unix variants from vendors including University of California, Berkeley ( BSD), Microsoft (Xenix), Sun Microsystems ( SunOS/ Solaris), HP/ HPE ( HP-UX), and IBM (AIX). In the early 1990s, AT&T sold its rights in Unix to Novell, which then sold the UNIX trademark to The Open Group, an industry consortium founded in 1996. The Open Group allows the use of the mark for certified operating systems that comply with the Single UNIX Specification (SUS). Unix systems are characterized by a modular design that is sometimes called the "Unix philosophy". According to th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Berkeley Software Distribution
The Berkeley Software Distribution or Berkeley Standard Distribution (BSD) is a discontinued operating system based on Research Unix, developed and distributed by the Computer Systems Research Group (CSRG) at the University of California, Berkeley. The term "BSD" commonly refers to its open-source descendants, including FreeBSD, OpenBSD, NetBSD, and DragonFly BSD. BSD was initially called Berkeley Unix because it was based on the source code of the original Unix developed at Bell Labs. In the 1980s, BSD was widely adopted by workstation vendors in the form of proprietary Unix variants such as DEC Ultrix and Sun Microsystems SunOS due to its permissive licensing and familiarity to many technology company founders and engineers. Although these proprietary BSD derivatives were largely superseded in the 1990s by UNIX SVR4 and OSF/1, later releases provided the basis for several open-source operating systems including FreeBSD, OpenBSD, NetBSD, DragonFly BSD, Darwi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cp (Unix)
In computing, cp is a command in various Unix and Unix-like operating systems for copying files and directories. The command has three principal modes of operation, expressed by the types of arguments presented to the program for copying a file to another file, one or more files to a directory, or for copying entire directories to another directory. The utility further accepts various command line option flags to detail the operations performed. The two major specifications are POSIX ''cp'' and GNU ''cp''. GNU ''cp'' has many additional options over the POSIX version. The command is also available in the EFI shell. History cp was part of Version 1 Unix. The version of cp bundled in GNU coreutils was written by Torbjorn Granlund, David MacKenzie, and Jim Meyering. Operating modes cp has three principal modes of operation. These modes are inferred from the type and count of arguments presented to the program upon invocation. *When the program has two arguments of path names t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cmp (Unix)
In computing, cmp is a command-line utility on Unix and Unix-like operating systems that compares two files of any type and writes the results to the standard output. By default, cmp is silent if the files are the same; if they differ, the byte and line number at which the first difference occurred is reported. The command is also available in the OS-9 shell. History is part of the X/Open Portability Guide since issue 2 of 1987. It was inherited into the first version of POSIX.1 and the Single Unix Specification. It first appeared in Version 1 Unix. The version of cmp bundled in GNU coreutils was written by Torbjorn Granlund and David MacKenzie. The command is available as a separate package for Microsoft Windows as part of the UnxUtils collection of native Win32 ports of common GNU Unix-like utilities. The command has also been ported to the IBM i operating system. Switches cmp may be qualified by the use of command-line switches. The switches supported by notable im ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chown
The command , an abbreviation of ''change owner'', is used on Unix and Unix-like operating systems to change the owner of file system files, directories. Unprivileged (regular) users who wish to change the group membership of a file that they own may use . The ownership of any file in the system may only be altered by a super-user. A user cannot ''give away'' ownership of a file, even when the user owns it. Similarly, only a member of a group can change a file's ''group ID'' to that group. The command is available as a separate package for Microsoft Windows as part of the UnxUtils collection of native Win32 ports of common GNU Unix-like utilities. The command has also been ported to the IBM i IBM i (the ''i'' standing for ''integrated'') is an operating system developed by IBM for IBM Power Systems. It was originally released in 1988 as OS/400, as the sole operating system of the IBM AS/400 line of systems. It was renamed to i5/OS i ... operating system. See also * ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chmod
In Unix and Unix-like operating systems, is the command and system call used to change the access permissions and the special mode flags (the ''setuid'', ''setgid'', and ''sticky'' flags) of file system objects ( files and directories). Collectively these were originally called its modes, and the name was chosen as an abbreviation of ''change mode''. History A command first appeared in AT&T UNIX version 1, along with the system call. As systems grew in number and types of users, access-control lists were added to many file systems in addition to these most basic modes to increase flexibility. The version of bundled in GNU coreutils was written by David MacKenzie and Jim Meyering. The command is available as a separate package for Microsoft Windows as part of the UnxUtils collection of native Win32 ports of common GNU Unix-like utilities. The command has also been ported to the IBM i operating system. Command syntax Throughout this section, ''ser'' refers to t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cd (command)
The command, also known as (change directory), is a command-line shell command used to change the current working directory in various operating systems. It can be used in shell scripts and batch files. Implementations The command has been implemented in operating systems such as Unix, DOS, IBM OS/2, MetaComCo TRIPOS, AmigaOS (where if a bare path is given, cd is ''implied''), Microsoft Windows, ReactOS, and Linux. On MS-DOS, it is available in versions 2 and later. DR DOS 6.0 also includes an implementation of the and commands. The command is also available in the open source MS-DOS emulator DOSBox and in the EFI shell. It is named in HP MPE/iX. The command is analogous to the Stratus OpenVOS command. is frequently included built directly into a command-line interpreter. This is the case in most of the Unix shells (Bourne shell, tcsh, bash, etc.), cmd.exe on Microsoft Windows NT/2000+ and Windows PowerShell on Windows 7+ and COMMAND.COM on DOS/ Microsoft ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cat (Unix)
cat is a standard Unix utility that reads files sequentially, writing them to standard output. The name is derived from its function to (con)catenate files (from Latin ''catenare'', "to chain"). It has been ported to a number of operating systems. History cat was part of the early versions of Unix, e.g., Version 1, and replaced pr, a PDP-7 and Multics utility for copying a single file to the screen. It was written by Ken Thompson and Dennis Ritchie. The version of cat bundled in GNU coreutils was written by Torbjorn Granlund and Richard Stallman. The ReactOS version was written by David Welch, Semyon Novikov, and Hermès Bélusca. Over time, alternative utilities such as tac and bat also became available, bringing different new features. Usage The Single Unix Specification defines the operation of cat to read files in the sequence given in its arguments, writing their contents to the standard output in the same sequence. The specification mandates the support of one option ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cal (command)
is a command-line utility on a number of computer operating systems including Unix, Plan 9, Inferno and Unix-like operating systems such as Linux that prints an ASCII calendar of the given month or year. If the user does not specify any command-line options, cal will print a calendar of the current month. The command is a standard program on Unix and specified in the Single UNIX Specification. Implementations The cal command was present in 1st Edition Unix. A cal command is also part of ASCII's ''MSX-DOS2 Tools'' for MSX-DOS version 2. It is also available for FreeDOS. This implementation only supports the Gregorian calendar (New Style) and may be distributed freely, with or without source. The FreeDOS version was developed by Charles Dye. Examples $ cal March 1984 Su Mo Tu We Th Fr Sa 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 $ cal -3 (shows the previous, current and next month ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
BCD (character Encoding)
BCD (''binary-coded decimal''), also called alphanumeric BCD, alphameric BCD, BCD Interchange Code, or BCDIC, is a family of representations of numerals, uppercase Latin letters, and some special and control characters as six-bit character codes. Unlike later encodings such as ASCII, BCD codes were not standardized. Different computer manufacturers, and even different product lines from the same manufacturer, often had their own variants, and sometimes included unique characters. Other six-bit encodings with completely different mappings, such as some FIELDATA variants or Transcode, are sometimes incorrectly termed BCD. Many variants of BCD encode the characters '0' through '9' as the corresponding binary values. History Technically, ''binary-coded decimal'' describes the encoding of decimal numbers where each decimal digit is represented by a fixed number of bits, usually four. With the introduction of the '' IBM card'' in 1928, IBM created a code capable of representing ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
As (Unix)
as is a generic command name for an assembler on Unix. Implementations More than one assembler for Unix and Unix-like operating systems has been implemented with an executable called as. Users may be able to determine which implementation (if any) is present on their system by consulting the system's manuals, or by running as --version. AT&T / Bell Labs As of November 1971, an assembler invoked as as was available for Unix. Implemented by Bell Labs staff, it was based upon the Digital Equipment Corporation's PAL-11R assembler. GNU Assembler Circa 1986, the GNU Assembler The GNU Assembler, commonly known as gas or as, is the assembler developed by the GNU Project. It is the default back-end of GCC. It is used to assemble the GNU operating system and the Linux kernel, and various other software. It is a part o ... ("GAS") became available. As with the original UNIX assembler, GAS's executable is simply named as. As of 2018, GAS implements many features that were not pre ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ar (Unix)
The archiver, also known simply as ar, is a Unix utility that maintains groups of files as a single archive file. Today, ar is generally used only to create and update static library files that the link editor or linker uses and for generating .deb packages for the Debian family; it can be used to create archives for any purpose, but has been largely replaced by tar for purposes other than static libraries. An implementation of ar is included as one of the GNU Binutils. In the Linux Standard Base (LSB), ar has been deprecated and is expected to disappear in a future release of that standard. The rationale provided was that "the LSB does not include software development utilities nor does it specify .o and .a file formats." File format details The ar format has never been standardized; modern archives are based on a common format with two main variants, BSD and System V (initially known as COFF, and used as well by GNU, ELF, and Windows.) Historically there have been other v ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
