sed question!

[bruce]

Hey guys.

Thanks for the delete replies..

Got a quick sed question now..

test file::
head -2  sed.dat
228d98f0_f16a_11e6_9544_1ad613f05f7b,1486934882
22b93712_f16a_11e6_a6ad_1ad613f05f7b,1486934883

want to simply truncate/search/replace the end of each line starting
with the ","
to get

228d98f0_f16a_11e6_9544_1ad613f05f7b
22b93712_f16a_11e6_a6ad_1ad613f05f7b

the following isn't working
 sed -i 's/\,+\$//'  sed.dat

 sed -i 's/\,+$//'  sed.dat

I'm sure it's simple/trivial...

thoughts...

[Gordon Messmer]

On 02/12/2017 05:06 PM, bruce wrote:
>  the following isn't working
>
>    sed -i 's/\,+$//'  sed.da 

That would remove one or more commas, if they immediately precede the 
end of the line.

You mean:

sed 's/,.*$//'

or:

cut -f1 -d,

[Fred Smith]

On Sun, Feb 12, 2017 at 08:06:28PM -0500, bruce wrote:
>  Hey guys.
>  
>  Thanks for the delete replies..
>  
>  Got a quick sed question now..
>  
>  test file::
>  head -2  sed.dat
>  228d98f0_f16a_11e6_9544_1ad613f05f7b,1486934882
>  22b93712_f16a_11e6_a6ad_1ad613f05f7b,1486934883
>  
>  want to simply truncate/search/replace the end of each line starting
>  with the ","
>  to get
>  
>  228d98f0_f16a_11e6_9544_1ad613f05f7b
>  22b93712_f16a_11e6_a6ad_1ad613f05f7b
>  
>  the following isn't working
>   sed -i 's/\,+\$//'  sed.dat
>  
>   sed -i 's/\,+$//'  sed.dat
>  
>  I'm sure it's simple/trivial... 
I'm far from a sed expert, but were I doing that I'd start with this,
and move on from there as required:

's/,.*$//'

which is: comma followed by zero or more of anything, followed by end of line.

I think your expression says:
one or more commas, followed by end of line.

Fred

-- 
---- Fred Smith -- fredex(a)fcshome.stoneham.ma.us -----------------------------
                      The eyes of the Lord are everywhere, 
                    keeping watch on the wicked and the good.
----------------------------- Proverbs 15:3 (niv) -----------------------------

[Clifford Snow]

I'm a awk user.
cat sed.dat | awk -F"," '{print $1}'

or

awk -F"," '{print $1}' sed.dat

On Sun, Feb 12, 2017 at 5:06 PM, bruce <badouglas(a)gmail.com&gt; wrote:

>  Hey guys.
>
>  Thanks for the delete replies..
>
>  Got a quick sed question now..
>
>  test file::
>  head -2  sed.dat
>  228d98f0_f16a_11e6_9544_1ad613f05f7b,1486934882
>  22b93712_f16a_11e6_a6ad_1ad613f05f7b,1486934883
>
>  want to simply truncate/search/replace the end of each line starting
>  with the ","
>  to get
>
>  228d98f0_f16a_11e6_9544_1ad613f05f7b
>  22b93712_f16a_11e6_a6ad_1ad613f05f7b
>
>  the following isn't working
>   sed -i 's/\,+\$//'  sed.dat
>
>   sed -i 's/\,+$//'  sed.dat
>
>  I'm sure it's simple/trivial...
>
>  thoughts...
>  _______________________________________________
>  users mailing list -- users(a)lists.fedoraproject.org
>  To unsubscribe send an email to users-leave(a)lists.fedoraproject.org
>  


-- 
@osm_seattle
osm_seattle.snowandsnow.us
OpenStreetMap: Maps with a human touch

[Steve Forsythe]

On 02/12/2017 08:06 PM, bruce wrote:
>  Hey guys.
>  
>  Thanks for the delete replies..
>  
>  Got a quick sed question now..
>  
>  test file::
>  head -2  sed.dat
>  228d98f0_f16a_11e6_9544_1ad613f05f7b,1486934882
>  22b93712_f16a_11e6_a6ad_1ad613f05f7b,1486934883
>  
>  want to simply truncate/search/replace the end of each line starting
>  with the ","
>  to get
>  
>  228d98f0_f16a_11e6_9544_1ad613f05f7b
>  22b93712_f16a_11e6_a6ad_1ad613f05f7b
>  
>  the following isn't working
>   sed -i 's/\,+\$//'  sed.dat
>  
>   sed -i 's/\,+$//'  sed.dat
>  
>  I'm sure it's simple/trivial...
>  
>  thoughts...
>  _______________________________________________
>  users mailing list -- users(a)lists.fedoraproject.org
>  To unsubscribe send an email to users-leave(a)lists.fedoraproject.org
>   
How about:
sed  's/,[0-9]\+$//' < sed.dat
228d98f0_f16a_11e6_9544_1ad613f05f7b
22b93712_f16a_11e6_a6ad_1ad613f05f7b

which removes a comma followed by 1 or more digits from the end of the
line. Or if you don't care what comes after the comma, then

sed  's/,.*$//' < sed.dat

will remove the comma and anything after it.

[Jon LaBadie]

On Sun, Feb 12, 2017 at 08:06:28PM -0500, bruce wrote:
>  Hey guys.
>  
>  Thanks for the delete replies..
>  
>  Got a quick sed question now..
>  
>  test file::
>  head -2  sed.dat
>  228d98f0_f16a_11e6_9544_1ad613f05f7b,1486934882
>  22b93712_f16a_11e6_a6ad_1ad613f05f7b,1486934883
>  
>  want to simply truncate/search/replace the end of each line starting
>  with the ","
>  to get
>  
>  228d98f0_f16a_11e6_9544_1ad613f05f7b
>  22b93712_f16a_11e6_a6ad_1ad613f05f7b
>  
>  the following isn't working
>   sed -i 's/\,+\$//'  sed.dat
>  
>   sed -i 's/\,+$//'  sed.dat
>  
>  I'm sure it's simple/trivial...
>   
Several problems.  The sed's I know don't use extended RE syntax
and '+' is a repetition character of extended RE.  Some sed's
might allow its use with the '-r' option.  And maybe there are
some sed's that do use extended RE.

Comma is not typically a special character, so no need to escape.

In pattern matching by the shell, the '*' repetition character
does not reference the preceeding character.  RE repetition
characters (* in basic and + and ? in extended) always refer
to repetitions of the preceeding character.  Thus your pattern
(if and extended RE) would be looking for a string of commas,
NOT one comma followed by a string of any char.

Try something like "sed -r -i 's/,[0-9]+$//'".
or "sed -i 's/,[0-9]*$//'" or if uncertain they
will be digits, but certain they will not be
commas (i.e. you want to delete the last comma
onward) try "sed -i 's/,[^,]*$//'

Jon
-- 
Jon H. LaBadie                  jonfu(a)jgcomp.com

[Cameron Simpson]

On 12Feb2017 20:06, bruce <badouglas(a)gmail.com&gt; wrote:
> Got a quick sed question now..
>
> test file::
> head -2  sed.dat
> 228d98f0_f16a_11e6_9544_1ad613f05f7b,1486934882
> 22b93712_f16a_11e6_a6ad_1ad613f05f7b,1486934883 
I always say "sed 2q" instead of "head -2", myself.

> want to simply truncate/search/replace the end of each line starting
> with the ","
> to get
>
> 228d98f0_f16a_11e6_9544_1ad613f05f7b
> 22b93712_f16a_11e6_a6ad_1ad613f05f7b
>
> the following isn't working
>  sed -i 's/\,+\$//'  sed.dat
>  sed -i 's/\,+$//'  sed.dat 
sed 's/,.*//'

1: You're in single quotes (generally desirable), so "," and "$"
are not shell 
special characters and need no backslashes.

2: I don't know what your intend with the "+" is. Firstly, by default sed
uses 
Basic Regular Expressions, which do not include "+". Secondly, "+" is
a regexp 
character meaning "1 or more or the preceeding item", so you're saying
"delete 
the first instance of one or more commas". Except that with BREs you're saying 
"delete the first comma followed by a plus" because "+" is not
special.

I'd test without the "-i" until you have things working.

Cheers,
Cameron Simpson <cs(a)zip.com.au&gt;