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Re: delimiters with more than one character? ...

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On 7/15/20 8:44 AM, Greg Wooledge wrote:
> On Wed, Jul 15, 2020 at 08:34:36AM -0400, Bob Weber wrote:
>> My only purpose was to show how tr could be used to handle multiple
>> characters as a delimiter either as tr -s '\\\|' '\|' or
> The problem is, it can't, at least not the way you showed.  The original
> example, sadly, did NOT contain instances of the | and \ characters in
> isolation, so one might be lulled into a false sense of security, and
> write code that (for example) simply deletes all of the \ characters,
> and then splits on the | characters.
>
> But that won't work in the general case, where | and \ might appear as
> literal data characters.
>
> My own solution, which involved using awk to convert the \| pairs into
> NUL bytes, is also technically incorrect.  However, there was an
> additional stipulation: the stream was to be converted into a bash
> array.  A bash array is a list of C strings, so they cannot contain
> NUL bytes.  Therefore you can't possibly have NUL bytes in the original
> input stream (at least, not and still produce a bash array), so my
> conversion of the multi-character delimiters into NUL bytes will "work".
>
> But it's a freaking ugly problem any way you look at it, and it just
> got uglier when it was revealed that the OP might be trying to write
> shell code that parses shell code.  Especially if the code in question
> is a series of poorly written GNU-tainted grep commands.
>
Which is why I showed this:

tr -s '\\\|' '\|'

which replaces \| with a single character which is known not to be in the input data and usable as a awk field separator.  It just happens to be a | which is ok with awk and and I have used as a separator in code over 30 years ago.

-- 


*...Bob*

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Thread

delimiters with more than one character? ... Albretch Mueller <lbrtchx@gmail.com> - 2020-07-14 15:00 +0200
  Re: delimiters with more than one character? ... Alex Mestiashvili <amestia@rsh2.donotuse.de> - 2020-07-14 15:00 +0200
    Re: delimiters with more than one character? ... Greg Wooledge <wooledg@eeg.ccf.org> - 2020-07-14 15:10 +0200
      Re: delimiters with more than one character? ... Nicolas George <george@nsup.org> - 2020-07-14 15:10 +0200
      Re: delimiters with more than one character? ... Alex Mestiashvili <amestia@rsh2.donotuse.de> - 2020-07-14 15:20 +0200
  Re: delimiters with more than one character? ... Greg Wooledge <wooledg@eeg.ccf.org> - 2020-07-14 15:10 +0200
  Re: delimiters with more than one character? ... Nicolas George <george@nsup.org> - 2020-07-14 15:20 +0200
  Re: delimiters with more than one character? ... Nicolas George <george@nsup.org> - 2020-07-14 17:30 +0200
    Re: delimiters with more than one character? ... Albretch Mueller <lbrtchx@gmail.com> - 2020-07-15 12:30 +0200
      Re: delimiters with more than one character? ... Greg Wooledge <wooledg@eeg.ccf.org> - 2020-07-15 14:00 +0200
      Re: delimiters with more than one character? ... David Wright <deblis@lionunicorn.co.uk> - 2020-07-15 14:30 +0200
      Re: delimiters with more than one character? ... Bob Weber <bobrweber@gmail.com> - 2020-07-15 14:40 +0200
        Re: delimiters with more than one character? ... Greg Wooledge <wooledg@eeg.ccf.org> - 2020-07-15 14:50 +0200
          Re: delimiters with more than one character? ... Bob Weber <bobrweber@gmail.com> - 2020-07-15 16:20 +0200
            Re: delimiters with more than one character? ... Greg Wooledge <wooledg@eeg.ccf.org> - 2020-07-15 16:30 +0200
            Re: delimiters with more than one character? ... The Wanderer <wanderer@fastmail.fm> - 2020-07-15 16:30 +0200
            Re: delimiters with more than one character? ... Nicolas George <george@nsup.org> - 2020-07-15 17:50 +0200
        Re: delimiters with more than one character? ... Nicolas George <george@nsup.org> - 2020-07-15 15:10 +0200
  Re: delimiters with more than one character? ... Bob Weber <bobrweber@gmail.com> - 2020-07-14 17:30 +0200
  Re: delimiters with more than one character? ... Alessandro Baggi <alessandro.baggi@gmail.com> - 2020-07-15 17:30 +0200
  Re: delimiters with more than one character? ... Eric S Fraga <e.fraga@ucl.ac.uk> - 2020-07-16 12:10 +0200
    Re: delimiters with more than one character? ... "Thomas Schmitt" <scdbackup@gmx.net> - 2020-07-16 13:40 +0200
      Re: delimiters with more than one character? ... Greg Wooledge <wooledg@eeg.ccf.org> - 2020-07-16 14:00 +0200
        Re: delimiters with more than one character? ... Greg Wooledge <wooledg@eeg.ccf.org> - 2020-07-16 16:00 +0200
          Re: delimiters with more than one character? ... Zenaan Harkness <zenaan@freedbms.net> - 2020-07-17 04:50 +0200
            Re: delimiters with more than one character? ... Nicolas George <george@nsup.org> - 2020-07-17 10:50 +0200
              Re: delimiters with more than one character? ... rhkramer@gmail.com - 2020-07-17 13:20 +0200
                tmpfs is not a ramdisk (was: delimiters with more than one  character? ...) Nicolas George <george@nsup.org> - 2020-07-17 13:30 +0200
                Re: tmpfs is not a ramdisk (was: delimiters with more than one  character? ...) David Wright <deblis@lionunicorn.co.uk> - 2020-07-17 18:20 +0200
                Re: tmpfs is not a ramdisk (was: delimiters with more than one character? ...) rhkramer@gmail.com - 2020-07-17 20:30 +0200
                Re: tmpfs is not a ramdisk (was: delimiters with more than one  character? ...) Zenaan Harkness <zenaan@freedbms.net> - 2020-07-18 07:20 +0200
                Re: tmpfs is not a ramdisk (was: delimiters with more than one  character? ...) <tomas@tuxteam.de> - 2020-07-18 10:40 +0200
                Re: delimiters with more than one character? ... Greg Wooledge <wooledg@eeg.ccf.org> - 2020-07-17 13:40 +0200
        Re: delimiters with more than one character? ... "Thomas Schmitt" <scdbackup@gmx.net> - 2020-07-16 16:00 +0200
        Re: delimiters with more than one character? ... Zenaan Harkness <zenaan@freedbms.net> - 2020-07-17 04:50 +0200
      Re: delimiters with more than one character? ... Eric S Fraga <e.fraga@ucl.ac.uk> - 2020-07-16 15:00 +0200
  Re: delimiters with more than one character? ... John Crawley <john@bunsenlabs.org> - 2020-08-05 08:30 +0200
    Re: delimiters with more than one character? ... Greg Wooledge <wooledg@eeg.ccf.org> - 2020-08-05 15:10 +0200
      Re: delimiters with more than one character? ... John Crawley <john@bunsenlabs.org> - 2020-08-06 05:00 +0200
        Re: delimiters with more than one character? ... Greg Wooledge <wooledg@eeg.ccf.org> - 2020-08-06 13:40 +0200
          Re: delimiters with more than one character? ... John Crawley <john@bunsenlabs.org> - 2020-08-07 03:10 +0200

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