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Re: Am I not seeing the Error?

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On Wed, Aug 14, 2013 at 7:59 AM, Joshua Landau <joshua@landau.ws> wrote:
> On 14 August 2013 02:20, Gregory Ewing <greg.ewing@canterbury.ac.nz> wrote:
>> Ned Batchelder wrote:
>>>
>>> Everyone: this program seems to be a direct and misguided transliteration
>>> from a bash script.
>>
>> Not a particularly well-written bash script, either --
>> it's full of superfluous uses of 'cat'.
>
> What's wrong with cat? Sure it's superfluous but what makes it *bad*?
> Personally I often prefer the pipe "cat x | y" form to "x < y"... or
> "< y x".

What's the use of it, in that situation? Why not simply use
redirection? (Though you have the letters backward; "cat y | x" would
be the equivalent of your others. Typo, I assume.) You're forking a
process that achieves nothing, if your cat has just one argument.

Of course, there ARE many good uses for cat. If you give it multiple
arguments, or if you have arguments that modify the output on the way
through (eg "cat -n"), then it's not the same as redirection. And some
programs behave differently if stdout is a tty, so the quickest way to
get the porcelain version of something is to append "|cat" to the
command. Or maybe you need to retrieve something that only root can
read, so you use "sudo cat /x/y/z|somescript". But if you could spell
it "x < y", then why not do so?

ChrisA

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Thread

Am I not seeing the Error? Devyn Collier Johnson <devyncjohnson@gmail.com> - 2013-08-10 22:19 -0400
  Re: Am I not seeing the Error? John Gordon <gordon@panix.com> - 2013-08-12 14:47 +0000
  Re: Am I not seeing the Error? Denis McMahon <denismfmcmahon@gmail.com> - 2013-08-13 20:28 +0000
    Re: Am I not seeing the Error? Dave Angel <davea@davea.name> - 2013-08-13 21:16 +0000
    Re: Am I not seeing the Error? MRAB <python@mrabarnett.plus.com> - 2013-08-14 00:44 +0100
    Re: Am I not seeing the Error? Ned Batchelder <ned@nedbatchelder.com> - 2013-08-13 20:00 -0400
      Re: Am I not seeing the Error? Gregory Ewing <greg.ewing@canterbury.ac.nz> - 2013-08-14 13:20 +1200
        Re: Am I not seeing the Error? Joshua Landau <joshua@landau.ws> - 2013-08-14 07:59 +0100
        Re: Am I not seeing the Error? Chris Angelico <rosuav@gmail.com> - 2013-08-14 13:07 +0100
          Re: Am I not seeing the Error? Roy Smith <roy@panix.com> - 2013-08-14 08:39 -0400
        Re: Am I not seeing the Error? Joshua Landau <joshua@landau.ws> - 2013-08-14 13:34 +0100

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