removing repeating/duplicate control char

peter sands

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Mar 15, 2013, 3:31:58 PM3/15/13

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Hello,

I have a text file where I need to get rid of a repeating control character, I have tried sed and tr but not getting the results I expect.
The text file is as an example:

^M
text here
text here
^M^M
text here
text here
^M

I need to remove the repeating character of ^M so I have:

^M
text here
text here
^M
text here
text here
^M

Any idea's please
PS

Aragorn

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Mar 15, 2013, 3:58:17 PM3/15/13

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On Friday 15 March 2013 20:31, peter sands conveyed the following to
comp.unix.shell...

sed 's/\^M//' FILE.IN > FILE.OUT

--
= Aragorn =

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Thomas 'PointedEars' Lahn

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Mar 15, 2013, 4:15:15 PM3/15/13

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What have you tried?

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PointedEars

Twitter: @PointedEars2
Please do not Cc: me. / Bitte keine Kopien per E-Mail.

Ben Bacarisse

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Mar 15, 2013, 10:05:56 PM3/15/13

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peter sands <peter...@techemail.com> writes:

> I have a text file where I need to get rid of a repeating control
> character, I have tried sed and tr but not getting the results I
> expect. The text file is as an example:
>
> ^M
> text here
> text here
> ^M^M
> text here
> text here
> ^M
>
> I need to remove the repeating character of ^M so I have:

If you know how to type a literal Ctrl+M at your shell is should be
obvious. On my system I type Ctrl+V before Ctrl+M. The Ctrl+V character
acts like a quote (it's called 'lnext' for 'literal next' in the tty
settings).

Now you can just type

tr -s ^M

or

sed -e s/^M^M*/^M/g

However, in tr you can write the character using tr's own escape
syntax so maybe the problem is not knowing what the character is?

<snip>
--
Ben.

Reinhard Skarbal

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Mar 16, 2013, 12:01:35 PM3/16/13

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"peter sands" <peter...@techemail.com> schrieb im Newsbeitrag
news:8fa0961c-0ddb-44ab...@googlegroups.com...

Hi Peter
Just from brain. Try
tr -d '\r' <infile >outfile

Regards
Reinhard

Barry Margolin

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Mar 16, 2013, 12:32:18 PM3/16/13

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In article <ki250q$v4n$1...@news.albasani.net>,

That will remove ALL ^M's from the file, he just wants to remove the
repeated ones.

--
Barry Margolin, bar...@alum.mit.edu
Arlington, MA
*** PLEASE post questions in newsgroups, not directly to me ***

Ben Bacarisse

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Mar 16, 2013, 4:55:17 PM3/16/13

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"Reinhard Skarbal" <reinhard...@aon.at> writes:

> "peter sands" <peter...@techemail.com> schrieb im Newsbeitrag
> news:8fa0961c-0ddb-44ab...@googlegroups.com...

<snip>

>> I need to remove the repeating character of ^M so I have:

<snip>

> Just from brain. Try
> tr -d '\r' <infile >outfile

tr -s '\r' <infile >outfile

The -s is for "squeeze" rather than -d for "delete" which is what the OP
wanted.

--
Ben.

spender

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Feb 20, 2023, 8:36:04 PM2/20/23

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USE sed command , find and replace: sed -n ':a;N;$!ba;s/\n\r\r\n/\n/g'
filename

Janis Papanagnou

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Feb 21, 2023, 4:03:58 AM2/21/23

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On 21.02.2023 02:35, spender wrote:
> 在 2013/3/16 3:31, peter sands 写道:

^^^^^^^^^^^

>> Hello,
>>
>> I have a text file where I need to get rid of a repeating control
>> character, I have tried sed and tr but not getting the results I expect.
>> The text file is as an example:

>> [...]

>
> USE sed command , find and replace: sed -n ':a;N;$!ba;s/\n\r\r\n/\n/g'
> filename

After these 10 years that passed since his post I suppose that peter
sands could have even carved the duplicate control characters out of
marble using a chisel instead of sed.

Janis