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# 1  
Old 12-17-2007
return the previous line
Hello friends ,

I am doing the following command, but it is not wise to all files.
Code:
for temp in `find ./CSV/ -name  "*.txt"`
do
          sed -n -e 'N; /*Main End/p' $temp
done

Its give me the correct output for some files , but not for all files.
I mean some files contains the string *Main End , But it wont return me any value . But In some files it contains the exact *Main End pattern , it returns me the previous line as usual.

Pls help..

I am using Solaris 6.0
# 2  
Old 12-17-2007
I think you misunderstand /*Main End/ as a regex.
Code:
/Main End$/ = Main End at the end of a line
/.*Main End/ = one or more of any character before Main End occurs  could be
   in the middle or at the end

The sed syntax is fine, it is your search expression causing your probelm.
# 3  
Old 12-17-2007
Quote:
Originally Posted by jim mcnamara
I think you misunderstand /*Main End/ as a regex.
Code:
/Main End$/ = Main End at the end of a line
/.*Main End/ = one or more of any character before Main End occurs  could be
   in the middle or at the end

The sed syntax is fine, it is your search expression causing your probelm.
Thanks for the reply.
But I opened in vi editor . And when I looked with the vi option
set list. It seems to be both same .

Ok. can you Please suggest me a R.E here for search the below
starting with a　* follwing Main End.

Thank you in advance..
# 4  
Old 12-18-2007
Strange output
Quote:
Originally Posted by user_prady
Thanks for the reply.
But I opened in vi editor . And when I looked with the vi option
set list. It seems to be both same .

Ok. can you Please suggest me a R.E here for search the below
starting with a　* follwing Main End.

Thank you in advance..
I ve two files looks as follows
file1
Code:
*Comment Frame 641 at 666.667 us
000000,CB1F,0,0,0,0,1,0,1
*Main End

file 2
Code:
000000,0000,0,0,2,0,0,0,0
*Comment Frame 
5,7E3D,0,0,0,0,1,0,1
*Main End

But when I using the command for both file
Code:
sed -n -e 'N; /\*Main End/p' file1

it should return me the line before The pattern *Main End

But it wont

But in case of file2 its working ,

Please need help urgently..
Last edited by user_prady; 12-18-2007 at 01:18 AM..
# 5  
Old 12-18-2007
Try:
sed -n -e '/\*Main End/{g;p;q;};h' file1

This returns only the line before the Main End line. Do you really need that Main End line as well? If so try this one:
sed -n -e '/\*Main End/{H;g;p;q;};h' file1
# 6  
Old 12-18-2007
Quote:
Originally Posted by Perderabo
Try:
sed -n -e '/\*Main End/{g;p;q;};h' file1

This returns only the line before the Main End line. Do you really need that Main End line as well? If so try this one:
sed -n -e '/\*Main End/{H;g;p;q;};h' file1
Thanks for the reply.
I am afraid, It wont return anything either of these..

I need only the previous line..
# 7  
Old 12-18-2007
Quote:
Originally Posted by user_prady
Thanks for the reply.
I am afraid, It wont return anything either of these..

I need only the previous line..
Excuse me? I just retested them on both of your data files. Both sed commands continue to work correctly for me on both of your files.

Code:
$ cat file1
*Comment Frame 641 at 666.667 us
000000,CB1F,0,0,0,0,1,0,1
*Main End
$ sed -n -e '/\*Main End/{H;g;p;q;};h' file1
000000,CB1F,0,0,0,0,1,0,1
*Main End
$ sed -n -e '/\*Main End/{g;p;q;};h' file1
000000,CB1F,0,0,0,0,1,0,1
$
$
$
$
$
$ cat file2
000000,0000,0,0,2,0,0,0,0
*Comment Frame
5,7E3D,0,0,0,0,1,0,1
*Main End
$ sed -n -e '/\*Main End/{H;g;p;q;};h' file2
5,7E3D,0,0,0,0,1,0,1
*Main End
$ sed -n -e '/\*Main End/{g;p;q;};h' file2
5,7E3D,0,0,0,0,1,0,1
$
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