What does linux rc mean?
linux rc is the abbreviation of runcom, and is also the rc that appears in ".cshrc" or "/etc/rc"; rc comes from runcom, which first appeared in the MIT CTSS system in 1965; in some scenarios , will execute multiple commands stored in the file, which we call runcom, which is the abbreviation of run commands.
What does linux rc mean?
The full meaning of Linux rc
This comes from the prehistoric era of the Unix system (1961 -1969), at the beginning, MIT developed a Compatible Time-Sharing System (CTSS). (Although the functions of this CTSS are not as good as those of later Unix systems, they are older and older.)
There is a feature about command scripts in the CTSS system called
runcom.
In order to pay tribute to the runcom feature of CTSS, an early version of Unix system,
rc was used as the startup file name of the operating system in later Unix systems.
Date in programming language starts from 1970-01-01,
You can also feel the "seniority" of the CTSS system from the side.
Meaning
rc =
RunCom
run commands, also called "runcom", and this kind of file is also called a runcom ( a runcom)."
Example
- .bashrc
bash running command
- .vimrc
Vim’s running command
- .npmrc
npm’s running command
. is expressed as Hidden files.
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
ReferenceWhat does rc mean in bashr, zshrc, vimrc etc?
What does rc mean in bashr, zshrc, vimrc etc? For the meaning of
rc, you may see the following:
- run commands
- resource control
- run control
- runtime configuration
rc is the abbreviation of
runcom.
rc = RunCom is the
rc# that appears in
.cshrc
or /etc/rc
##rc
comes from runcom
, which first appeared in the MIT CTSS system in 1965. In some scenarios, (we) will execute multiple commands
stored in the file, which we call runcom
that is, running commands## Abbreviation for #run commands.
In addition, the file used to store commands is called: a runcom
.
The rc
in Unix file naming comes from this old allusion.
— Brian Kernighan & Dennis Ritchie, as told to Vicki BrownAlso ESR states that in Run-Control Files:
Evidence is found in:
rc
The suffix is traced back all the way, and you will find that it actually exists in CTSS, the granddaddy of Unix systems. In the ancient system of CTSS, there is a command script feature called:
runcom
. So in the early days of Unix,
rc
was used as the file name of the operating system startup script to recall/pay tribute to CTSS runcom. So I think:
rc is the abbreviation of
runcom
<h2>
<a id="CTSSCompatible_TimeSharing_System_70"></a>CTSS(Compatible Time-Sharing System)兼容分时系统</h2>
<p>Unix系统的背景<br> 1961-1969:史前时代<br> CTSS(Compatible Time-Sharing System,兼容分时系统),以MIT为首的开发小组,小而简单的实验室原型。<br> Multics(Multiplexed Information and Computing System,多路信息与计算系统),庞大而负责,不堪重负。<br> Unics(Uniplexed information and Computing System,单路信息与计算系统),返璞归真,走上正道。<br> 1969-1971:创世纪<br> ……</p>
<h2>
<a id="_Unix__Frequently_Asked_Questions_17_Frequent_postingSection__What_does_some_strange_unix_command_name_stand_for_82"></a>参考 Unix - Frequently Asked Questions (1/7) [Frequent posting]Section - What does {some strange unix command name} stand for</h2>
<pre class="brush:php;toolbar:false">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.</pre>
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