Backtick versus $()

Chad Perrin perrin at apotheon.com
Fri Feb 25 01:37:03 UTC 2011


On Thu, Feb 24, 2011 at 08:14:55PM -0430, Andres Perera wrote:
> On Thu, Feb 24, 2011 at 7:56 PM, Chad Perrin wrote:
> >
> > I'll try to help make it easy for you, since you seem to be having a
> > lot of trouble grasping the concept of actually trying to make a
> > point via logical argument and presentation of evidence:
> >
> > Start with the Wikipedia page comparing command shells [0].  Look
> > through the various tables there -- feel free to ignore the
> > "Programming features" table since it's irrelevant to the question of
> > what makes a good interactive user shell -- to see where shells
> > differ.  Based on the differences you find, build up a list of
> > reasons that tcsh is not as good a choice as mksh.
> 
> no, let's start by looking at the SOURCE CODE REPOSITORY instead of
> WIKIPEDIA

If you find something inaccurate there, feel free to dispute it.  I don't
mind that at all.  I was just offering you a place to start (which is all
an encyclopedia is anyway; never treat it as the final word).  If that's
too difficult for you to understand, I'll try to avoid holding it against
you.


> 
> you DROOLING BUFFOON

I might hold *that* against you, though -- even if it just hurts *you* in
this community, rather than me.


> >
> > Next, offer some examples of common command line syntax rules and how
> > they affect the way we compose commands.  Such examples should
> > include stuff like:
> >
> > * environment variable assignment, printing, and export
> 
> export is the same as environment variable assignment in this context

It is not always the same.  Define "this context" so that your statement
makes more sense, please.


> 
> why is this relevant to interactive shells and not scripting?

Have you never, ever set an environment variable temporarily within an
interactive shell -- such as when using make?  How little do you actually
use a shell to not realize that this might be relevant to interactive
shell preference?


> >
> > * nesting commands
> 
> "nesting" commands? another programming paradigm?

Nope.  It's something people sometimes do when issuing shell commands.
Have you never used backticks or dollar-parentheses to nest commands?


> >
> > * completion and history access
> 
> modern ksh variants include file completion, tcsh does arbitrary
> completion through aliases

I don't see any examples here.


> 
> the second is arguably misguided since unix is file-centric, not
> --long-option-centric

What does that have to do with it?


> >
> > * useful configuration file characteristics and capabilities
> 
> define "useful"

I guess that might be up to you, to some extent.  I was just trying to
offer you ideas for how to make a reasoned response, rather than go on
ranting without substance.


> >
> > Then, of course, you can go on to further strengthen your case with
> > references to dependencies, licensing, resource consumption and
> > on-drive size, bugs, and so on.
> 
> no, bugs is the primary concern because the underlying design is more
> important than having flashy lights
> 
> if you disagree then you are retarded and the exchange concludes

Whether I agree with it or not is irrelevant, since you have not
mentioned any bugs.

. . . and whether bugs are the biggest problem in no way proves that
other problems do not exist or are not relevant.


> 
> just explicitly say it: "i don't care if the shell is bugged from hell
> and back"

I think you mean "to hell and back".

. . . and I never said I don't care if it's buggy.  You also haven't
started listing bugs, so it's a moot point.

Pay close attention to this next paragraph:

> >
> > Any of this stuff might actually present a meaningful argument, as
> > opposed to just asserting other people are idiots, claiming you're
> > right with nothing to back it up, and generally waving your hands and
> > making a lot of noise without convincing anyone of anything.

Notice you still have not bothered to offer anything substantive.  I
essentially gave you a howto, and you still managed to fail.  I get the
impression you actually do not know anything about these shells that you
have not already said, and are (in effect) screaming invective at me to
avoid having to admit you have no reasonable argument to offer.  Your
most meaningful arguments so far are claims that I drool.  Unfortunately,
it is very difficult to prove a negative, so I have no evidence to
support my assertion that, in the general case, I certainly do not drool.

-- 
Chad Perrin [ original content licensed OWL: http://owl.apotheon.org ]
-------------- next part --------------
A non-text attachment was scrubbed...
Name: not available
Type: application/pgp-signature
Size: 196 bytes
Desc: not available
Url : http://lists.freebsd.org/pipermail/freebsd-questions/attachments/20110225/6c2c0275/attachment.pgp


More information about the freebsd-questions mailing list