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9

RFC 1945 (1996) says 5.1.1 Method The Method token indicates the method to be performed on the resource identified by the Request-URI. The method is case-sensitive. Method = "GET" ; Section 8.1 | "HEAD" ; Section 8.2 | "POST" ; Section 8.3 ...


1

This is probably just a result from the definition of those operations in the RFC using all caps. For other (older) protocols, even if the actual implementation might not be case sensitive, the operations' description in RFC is in all caps as well. It might be because that makes them stand out in the text only documents in which there is no other way to ...


0

find is not a simple command that is controlled by options but a command that implements an own control language. The find CLI looks like: find [options] path1..pathn [expression] Where options are e.g. -H, -L, -P and expression is a script written in the find control language. The parameters like -name are called: primaries, because they are primary ...


2

find and cpio were created by Dick Haight and not by the people who wrote most of the orginal Unix utilities. There was no commandline argument parsing library at the time that you could link as a library, and that would enforce/stimulate some consistency (in the mid 80s I had source code for getopt on several systems ) Once people use commands and their ...


2

You seem to have confused a few things. Neither find nor cp are shell builtins. The only argument in the find command is the path, the rest are options and their values, but that's just semantics, the distinction here is not very important. More importantly, there are two classes of option flags. Those that take arguments and those that don't. For those that ...


4

The commands came first, consistency was added later. The earliest manpage you're likely to find shows it as find pathname expression find dates back to the 1970s, and the assumptions of ordering and even syntax (whether a dash is needed for options) were added to various commands later (say during the later 1980s and early 1990s) to help users remember ...


0

It's an efficiency measure. The CPU runs so much faster than the serial port that if the kernel let the userspace process run every time there was a little bit of room in the buffer, it would end up making a trip to userspace and back for every single byte of data. That's very wasteful of CPU time: $ time dd if=/dev/zero of=/dev/null bs=1 count=10000000 ...


1

Yes, we have two different ways for comparing two integers. It seems that this facts are not widely accepted in this forum: Inside the idiom [ ] the operators for arithmetic comparison are -eq, -ne, -lt, -le, -gt and -ge. As they also are inside a test command and inside a [[ ]]. Yes inside this idioms, =, <, etc. are string operators. Inside the ...


1

Historically, the test command existed first (at least as far back to Unix Seventh Edition in 1979). It used the operators = and != to compare strings, and -eq, -ne, -lt, etc. to compare numbers. For example, test 0 = 00 is false, but test 0 -eq 00 is true. I don't know why this syntax was chosen, but it may have been to avoid using < and >, which the ...


0

According to the test man page, = and != are used for string comparisons while the expressions -eq, -gt, -lt, -ge, -le, and -ne are integer comparisons. I've always followed this convention when writing shell scripts and it always works. Be aware that if you have variables in the expression, you may need to quote the variables in some way to avoid doing a ...


3

The GNU project chose its recursive acronym for "GNU's Not Unix!" because GNU's design is Unix-like, but differs from it by being free software (while the original Unix was closed-source) and containing no original Unix code (i.e. has been entirely rewritten).


7

Ctrl+R works with ksh in emacs mode (ksh -o emacs or set -o emacs within ksh), and it was most probably the first shell to support it. Only it's not as interactive as in zsh or bash or tcsh's i-search-back widget. In ksh (both ksh88 and ksh93), you type Ctrl+RtextReturn. And Ctrl+RReturn to search again with the same text. In vi mode, you can use ? to ...


4

The Korn shell does support history searches using CtrlR, at least since ksh93 (and perhaps even ksh88), but they don't work quite like bash. First you need to enable Emacs mode: set -o emacs (This enables other niceties, such as arrow keys working by default.) Now if you press CtrlR, the shell will print ^R; type your search, hit Enter, and the shell ...


-1

In the 1970s there was no cursor editable history for shells. The first shell with integrated cursor editable history was my bsh in 1984 (based on a prototype from 1982). This history implementation uses crontrol-r to redisplay the current commandline. In 1986, the Korn Shell became a member of the group of shells that implement a fully integrated cursor ...


2

The IBM System/360 that OS/360 ran on didn't have virtual memory so all batch jobs ran in one address space and there was very little protection between jobs. There wasn't any real concept of processes. The System/370 introduced in 1970 did have virtual memory so it was possible to have things like processes although I don't recall that term being used by ...


2

For Free and/or Open software logos are often based on animals. GNU stands for GNU is Not Unix and the match with the animal is quickly made. See http://www.gnu.org/ and http://www.gnu.org/gnu/gnu.html for more information.


5

The common name of the animal in GNU Project's logo is gnu and it is a species of antelope (also called wildebeest). The acronym GNU (Gnu's Not Unix) was introduced in 1983 in a text email by Richard Stallman. It can be assumed that the acronym GNU precedes the logo and its spelling became an inspiration for the design. The original logo (called A GNU ...


2

I cannot provide proof of any kind, but Ctrl-P and Ctrl-N belong to the emacs key bindings, in contrast to vi bindings (bindkey -e vs. bindkey -v). Under this premise, you should look for an explanation in emacs itself. emacs' tutorial tells There are several ways you can do this. You can use the arrow keys, but it's more efficient to keep your ...


0

LZMA2 is a block compression system whereas gzip is not. This means that LZMA2 lends itself to multi-threading. Also, if corruption occurs in an archive, you can generally recover data from subsequent blocks with LZMA2 but you cannot do this with gzip. In practice, you lose the entire archive with gzip subsequent to the corrupted block. With an LZMA2 ...


2

Mikel is right. From this post on Google Groups' group for CS246 at the University of Waterloo: Don't let the /xhbin part spook you. This is a peculiarity of the MFCF/CSCF environment. I don't know all of the details, but some time ago MFCF developed a program called xhier to make it easier to distribute software to a large number of machines. ...


0

According to wikipedia System V was preceded by System III, a release of UNIX/TS 3. Since there were no official release of UNIX/TS 4, System III was superseded directly by System V.


3

Depending on the source (and weight you may attach), shar dates back to around 1980. In a form which you might recognize, that comes from Rich Salz's implementation introduced in 1988, and improved in stages over the next few years. shar was originally a convenience for bundling text files. uuencoding (a way to send binary files) has been around at least ...


2

You are mistaken, shell archivers did exist no later than 1980. They have been written for the usenet source archives in order to allow the archives to appear inside a mail. Tar is binary and cannot easily be in a usenet source archive.



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