linux rc的含義是什么

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本篇內容主要講解“linux rc 的含義是什么”，感興趣的朋友不妨來看看。本文介紹的方法操作簡單快捷，實用性強。下面就讓丸趣 TV 小編來帶大家學習“linux rc 的含義是什么”吧!

linux rc 是 runcom 的縮寫，也是“.cshrc”或“/etc/rc”中出現的 rc；rc 來源于 runcom，首次出現于 1965 年的 MIT CTSS 系統；在某些場景中，會執行被存儲在文件中的多條命令 commands，我們稱之為 runcom，即運行命令 run commands 的簡稱。

Linux rc 含義全稱

這要從 Unix 系統的史前時代 (1961-1969) 開始講起，在一開始由 MIT 為主力開發過一個兼容分時系統(Compatible Time-Sharing System)，簡稱 CTSS。
（這個 CTSS 他功能雖然比不了后來的 Unix 系統，但是人家輩分大，年代早。）
CTSS 系統中有一個關于命令腳本的特性叫做 runcom。
為了致敬這個古早版本 Unix 系統——CTSS 的 runcom 特性，后來的 Unix 系統中就用 rc 作為操作系統的啟動文件名。

Tips
程序語言里的 Date 是從 1970-01-01 開始的，

而前面提到的 Unix 的史前時代 (1961-1969) 還在 1970 年之前。
也可以側面感受到 CTSS 這個系統的“輩分”之大。

含義

rc = RunCom

“rc”是取自“runcom”, 來自麻省理工學院在 1965 年發展的 CTSS 系統。相關文獻曾記載這一段話：“具有從檔案中取出一系列命令來執行的功能；這稱為 run commands 又稱為“runcom”，而這種檔案又稱為一個 runcom (a runcom)。”

實例

.bashrc bash 的運行命令

.vimrc vim 的運行命令

.npmrc npm 的運行命令

Linux 中，文件名以. 開頭表示為隱藏文件。

leung@wuyujin ~ % ls -al | grep rc$
-rw-------   1 leung  staff      33  5 13 20:34 .npmrc
-rw-r--r--   1 leung  staff     116  5 13 21:20 .yarnrc
-rw-r--r--   1 leung  staff      55  6  2 20:00 .zshrc

參考 What does rc mean in bashr, zshrc, vimrc etc?

What does rc mean in bashr, zshrc, vimrc etc?

翻譯如下：
對于 rc 所代表的意思，你可能會看到以下幾種：

run commands(運行命令)

resource control(資源控制)

run control(運行控制)

runtime configuration(運行時配置)

在讀過這份文檔之后，我更愿意認為 rc 是 runcom 的縮寫。

rc = RunCom 就是.cshrc 或 /etc/rc 中出現的那個 rc
rc 來源于 runcom，首次出現于 1965 年的 MIT CTSS 系統。

在某些場景中，(我們)會執行被存儲在文件中的多條命令 commands，我們稱之為 runcom 即運行命令 run commands 的簡稱。
另外，這個用于存儲命令的文件被稱作：a runcom。
Unix 文件命名中的 rc 就是來自于這樣的老典故。
— Brian Kernighan Dennis Ritchie, as told to Vicki Brown

Also ESR states that in Run-Control Files:
當然，你也可以在 Run-Control 文件中找到證據：
rc 后綴一直往前追溯，會發現其實它在 Unix 的爺爺輩老系統——CTSS 里就有了。
而在 CTSS 這個古早的系統中有一個命令腳本的特性叫做：runcom。
于是早期 Unix 就開始使用 rc 作為操作系統啟動腳本的文件名，以此來追憶 / 致敬 CTSS runcom。

所以我認為：rc 是 runcom 的縮寫。

CTSS(Compatible Time-Sharing System)兼容分時系統

Unix 系統的背景
1961-1969：史前時代
CTSS(Compatible Time-Sharing System，兼容分時系統)，以 MIT 為首的開發小組，小而簡單的實驗室原型。
Multics(Multiplexed Information and Computing System，多路信息與計算系統)，龐大而負責，不堪重負。
Unics(Uniplexed information and Computing System，單路信息與計算系統)，返璞歸真，走上正道。
1969-1971：創世紀
……

參考 Unix – Frequently Asked Questions (1/7) [Frequent posting]Section – What does {some strange unix command name} stand for

1.3)  What does {some strange unix command name} stand for?

      awk = Aho Weinberger and Kernighan 

        This language was named by its authors, Al Aho, Peter
        Weinberger and Brian Kernighan.

      grep = Global Regular Expression Print 

        grep comes from the ed command to print all lines matching a
        certain pattern

                    g/re/p

        where re is a regular expression .

      fgrep = Fixed GREP .

        fgrep searches for fixed strings only.  The f does not stand
        for fast - in fact, fgrep foobar *.c is usually slower than
         egrep foobar *.c  (Yes, this is kind of surprising. Try it.)

        Fgrep still has its uses though, and may be useful when searching
        a file for a larger number of strings than egrep can handle.

      egrep = Extended GREP 

        egrep uses fancier regular expressions than grep.  Many people
        use egrep all the time, since it has some more sophisticated
        internal algorithms than grep or fgrep, and is usually the
        fastest of the three programs.

      cat = CATenate 

        catenate is an obscure word meaning to connect in a series ,
        which is what the cat command does to one or more files.  Not
        to be confused with C/A/T, the Computer Aided Typesetter.

      gecos = General Electric Comprehensive Operating Supervisor 
        
        When GE s large systems division was sold to Honeywell,
        Honeywell dropped the E from GECOS .

        Unix s password file has a pw_gecos field.  The name is a
        real holdover from the early days.  Dennis Ritchie has reported:

             Sometimes we sent printer output or batch jobs
             to the GCOS machine.  The gcos field in the password file
             was a place to stash the information for the $IDENT card.
             Not elegant. 

      nroff = New ROFF 
      troff = Typesetter new ROFF 
        
        These are descendants of roff , which was a re-implementation
        of the Multics runoff program (a program that you d use to
         run off a good copy of a document).

      tee       = T

        From plumbing terminology for a T-shaped pipe splitter.

      bss = Block Started by Symbol 
        
        Dennis Ritchie says:

            Actually the acronym (in the sense we took it up; it may
            have other credible etymologies) is Block Started by
            Symbol. It was a pseudo-op in FAP (Fortran Assembly [-er?]
            Program), an assembler for the IBM 704-709-7090-7094
            machines.  It defined its label and set aside space for a
            given number of words.  There was another pseudo-op, BES,
             Block Ended by Symbol that did the same except that the
            label was defined by the last assigned word + 1.  (On these
            machines Fortran arrays were stored backwards in storage
            and were 1-origin.)

            The usage is reasonably appropriate, because just as with
            standard Unix loaders, the space assigned didn t have to be
            punched literally into the object deck but was represented
            by a count somewhere.

      biff = BIFF 

        This command, which turns on asynchronous mail notification,
        was actually named after a dog at Berkeley.

            I can confirm the origin of biff, if you re interested.
            Biff was Heidi Stettner s dog, back when Heidi (and I, and
            Bill Joy) were all grad students at U.C. Berkeley and the
            early versions of BSD were being developed.   Biff was
            popular among the residents of Evans Hall, and was known
            for barking at the mailman, hence the name of the command.

        Confirmation courtesy of Eric Cooper, Carnegie Mellon University

      rc (as in .cshrc or /etc/rc) = RunCom 

         rc derives from runcom , from the MIT CTSS system, ca. 1965.

             There was a facility that would execute a bunch of
            commands stored in a file; it was called runcom for run
            commands , and the file began to be called a runcom. 

             rc in Unix is a fossil from that usage. 
        
        Brian Kernighan Dennis Ritchie, as told to Vicki Brown

         rc is also the name of the shell from the new Plan 9
        operating system.

      Perl = Practical Extraction and Report Language 
      Perl = Pathologically Eclectic Rubbish Lister 

        The Perl language is Larry Wall s highly popular
        freely-available completely portable text, process, and file
        manipulation tool that bridges the gap between shell and C
        programming (or between doing it on the command line and
        pulling your hair out).  For further information, see the
        Usenet newsgroup comp.lang.perl.misc.

      Don Libes book Life with Unix contains lots more of these
      tidbits.