Login or Register to Ask a Question and Join Our Community


Shell Programming and Scripting

print chunk of lines only if there is a pattern match in between them

Login to Discuss or Reply to this Discussion in Our Community

 
Thread Tools Search this Thread
Top Forums Shell Programming and Scripting print chunk of lines only if there is a pattern match in between them
# 1  
Old 02-18-2011
Question print chunk of lines only if there is a pattern match in between them
Hi All,
Please find the sample file below:
Code:
NAME                                                                                               ID NUMBER
--------------------------------------------------------------------------------------------------       ---------
abcdefgheija;lksdf                                                                                 11000000 
*** LOCKED *** 
    PARENT                            3887                                                        
    TRAN NO:                                03                                                      
    PARENT 
    PARENT 
NAME                                                                                               ID NUMBER
-------------------------------------------------------------------------------------------------- ---------
bbcdeqgheija;lksdf                                                                                 11300000 
                                            
    DATE:                            02-MAR-2010                                     
    SOURCE CORRECTION:                      Y                                                             
NAME                                                                                               ID NUMBER
-------------------------------------------------------------------------------------------------- ---------
vbcdewgheija;lksdf                                                                                 10200000 
                                           
    DATE:                            15-DEC-2010                                      
    
NAME                                                                                               ID NUMBER
-------------------------------------------------------------------------------------------------- ---------
cvbcdeegheija;lksdf                                                                                10300000 
                                           
*** LOCKED *** 
    MIDDLE INITIAL:                                                                                    
    DATE:                            03-JUN-2010                      
<<<<< EOF>>>>

I am trying to print the lines starting from name till next name is encountered, but only if "LOCKED" term is present in the details of that person.

Any input or psuedocode in Perl script is welcome. Right now my code is either printing the whole file or the lines with LOCKED term.

Thanks in advance,
Niel.
Last edited by Scott; 02-18-2011 at 02:00 PM.. Reason: Please use code tags
# 2  
Old 02-18-2011
Try:
Code:
perl -n0e 'while (/NAME.*?((?=NAME)|(?=$))/sg) {$x=$&;print $x if $x=~/LOCKED/}' file

# 3  
Old 02-18-2011
@Bartus11, thanks
Hi Bartus11,
thanks very much for the code.
I am new to Perl, it would be greatly helpful if you could please explain me your code.

Thanks,
Niel.
# 4  
Old 02-18-2011
Would something kludgy work?:

Code:
grep -B4 -A3 LOCKED <file>

Play with the -B (before) and -A (after)
Last edited by radoulov; 02-24-2011 at 05:30 PM.. Reason: Code tags, please!
# 5  
Old 02-18-2011
Quote:
Originally Posted by niel.verty
Hi Bartus11,
thanks very much for the code.
I am new to Perl, it would be greatly helpful if you could please explain me your code.

Thanks,
Niel.
Well I don't know if it would make much sense, because this code is using some quite advanced regex techniques, like look ahead or sequential matching, which require some regex understanding. If you are still interested I can break it down for you.

After giving it a bit of thought I decided to do it anyway Smilie
Code:
perl -n0e 'while (/NAME.*?((?=NAME)|(?=$))/sg) {$x=$&;print $x if $x=~/LOCKED/}' file

-n - load file's contents into $_ variable
-0 - load whole file into $_ variable. Without that perl would divide the file into lines and process them one by one
-e - execute script
while (/NAME.*?((?=NAME)|(?=$))/sg) - keep going through $_ variable (g option), matching blocks of it that start with "NAME" and that have "NAME" right after their end. This is the look ahead part (?=NAME). To match also last block in variable (file), which is starting with "NAME", but there is no "NAME" at the end, there is alternative look ahead match (?=$), that means end of the variable. /s regex option allows . to match newline characters, which allow regex to match through multiple lines. .*? matches non-greedily all the characters that are between "NAME" and before next "NAME". If ? was missing in this expression, regex would perform greedy match, which would match whole variable in single run. While's body is quite easy. $x=$& is assigning recent match to $x variable. It is done to avoid loosing it's contents when /LOCKED/ is run. So now $x consist of block of lines extracted from $_ variable (file's contents), that start with "NAME" and ends just before next "NAME". This block is tested by $x=~/LOCKED/ expression, to check if it contains word LOCKED, and if it does, then print $x is printing it on screen.
Last edited by bartus11; 02-18-2011 at 06:15 PM..
This User Gave Thanks to bartus11 For This Post:
niel.verty
# 6  
Old 02-19-2011
cgrep for regular-expression-context grep situations
Hi.

The non-standard utility cgrep -- "context grep" -- may be easier to understand. You probably know that standard GNU grep allows previous and subsequent lines around the matched line to be listed. The cgrep allows you to specify the limits of a window to print around the matched line. The limits can themselves be regular expressions. So:
Code:
cgrep pattern filename

works just like GNU grep, but
Code:
cgrep -w beginning-of-window-pattern +w end-of-window-pattern main-pattern filename

will extract blocks of text that contain main-pattern.

Here is a demo script that uses a width-decreased version of your data, and the core of the script uses cgrep as noted above. The other lines are supporting code, showing the data, environment, versions, etc.
Code:
#!/usr/bin/env bash

# @(#) s1	Demonstrate block extraction with embedded match constraint.
# cgrep home: http://sourceforge.net/projects/cgrep/

# Section 1, setup, pre-solution.
# Infrastructure details, environment, commands for forum posts. 
# Uncomment export command to test script as external user.
# export PATH="/usr/local/bin:/usr/bin:/bin"
set +o nounset
pe() { for i;do printf "%s" "$i";done; printf "\n"; }
pl() { pe;pe "-----" ;pe "$*"; }
C=$HOME/bin/context && [ -f $C ] && . $C cgrep
set -o nounset
pe

FILE=${1-data1}
# cut width to look better in demo.
cut -c 1-78 data0 > $FILE

# Section 2, display input file.
# Display sample of data file, with head & tail as a last resort.
pe " || start [ first:middle:last ]"
specimen $FILE \
|| { pe "(head/tail)"; head -n 5 $FILE; pe " ||"; tail -n 5 $FILE; }
pe " || end"

# Section 3, solution.
pl " Results:"
cgrep -D -w NAME +w NAME LOCKED $FILE

exit 0

producing:
Code:
% ./s1

Environment: LC_ALL = C, LANG = C
(Versions displayed with local utility "version")
OS, ker|rel, machine: Linux, 2.6.26-2-amd64, x86_64
Distribution        : Debian GNU/Linux 5.0.7 (lenny) 
GNU bash 3.2.39
cgrep - (local: ~/executable/cgrep May 29 2009 )

 || start [ first:middle:last ]
Edges: 5:0:5 of 28 lines in file "data1"
NAME                                                                          
------------------------------------------------------------------------------
abcdefgheija;lksdf                                                            
*** LOCKED *** 
    PARENT                            3887                                    
   ---
                                           
*** LOCKED *** 
    MIDDLE INITIAL:                                                           
    DATE:                            03-JUN-2010                      
<<<<< EOF>>>>
 || end

-----
 Results:
NAME                                                                          
------------------------------------------------------------------------------
abcdefgheija;lksdf                                                            
*** LOCKED *** 
    PARENT                            3887                                    
    TRAN NO:                                03                                
    PARENT 
    PARENT 
NAME                                                                          
NAME                                                                          
------------------------------------------------------------------------------
cvbcdeegheija;lksdf                                                           
                                           
*** LOCKED *** 
    MIDDLE INITIAL:                                                           
    DATE:                            03-JUN-2010                      
<<<<< EOF>>>>

The code needs to be obtained from cgrep | Download cgrep software for free at SourceForge.net and compiled with a "c" compiler. I have done it on 32-bit and 64-bit systems without trouble. I have found cgrep to be very useful in situations like this.

Good luck ... cheers, drl

( Edit 1: clarification, minor typo )
Last edited by drl; 02-20-2011 at 07:36 AM..
These 2 Users Gave Thanks to drl For This Post:
niel.verty radoulov
# 7  
Old 02-19-2011
Code:
awk '/NAME/{if(l)print s;l=0;s=$0;next}/LOCKED/{l=1}{s=s RS $0}END{if(l)print s}' infile
Login or Register to Ask a Question

Previous Thread | Next Thread

10 More Discussions You Might Find Interesting

1. Shell Programming and Scripting

sed -- Find pattern -- print remainder -- plus lines up to pattern -- Minus pattern

The intended result should be : PDF converters 'empty line' gpdftext and pdftotext?xml version="1.0"?> xml:space="preserve"><note-content version="0.1" xmlns:/tomboy/link" xmlns:size="http://beatniksoftware.com/tomboy/size">PDF converters gpdftext and pdftotext</note-content>... (9 Replies)
Discussion started by: Klasform
9 Replies

2. Shell Programming and Scripting

Match Pattern and print pattern and multiple lines into one line

Hello Experts , require help . See below output: File inputs ------------------------------------------ Server Host = mike id rl images allocated last updated density vimages expiration last read <------- STATUS ------->... (4 Replies)
Discussion started by: tigerhills
4 Replies

3. UNIX for Dummies Questions & Answers

Match Pattern after certain pattern and Print words next to Pattern

Hi experts , im new to Unix,AWK ,and im just not able to get this right. I need to match for some patterns if it matches I need to print the next few words to it.. I have only three such conditions to match… But I need to print only those words that comes after satisfying the first condition..... (2 Replies)
Discussion started by: 100bees
2 Replies

4. Shell Programming and Scripting

awk print pattern match line and following lines

Data: Pattern Data Data Data Data Data Data Data Data Data ... With awk, how do I print the pattern matching line, then the subsequent lines following the pattern matching line. Varying number of lines following the pattern matching line. (9 Replies)
Discussion started by: dmesserly
9 Replies

5. Shell Programming and Scripting

Print lines that do not match the pattern

I need to print the lines that do not match a pattern. I tried using grep -v and sed -n '/pattern/!p', but both of them are not working as I am passing the pattern as variable and it can be null some times. Example ........ abcd...... .........abcd...... .........abcd......... (4 Replies)
Discussion started by: sunny1234
4 Replies

6. Shell Programming and Scripting

Need one liner to search pattern and print everything expect 6 lines from where pattern match made

i need to search for a pattern from a big file and print everything expect the next 6 lines from where the pattern match was made. (8 Replies)
Discussion started by: chidori
8 Replies

7. Shell Programming and Scripting

Print lines before and after pattern match

I am using Solaris, I want to print 3 lines before pattern match pattern 5 lines after pattern match Pattern is abcd to be searched in a.txt. Looking for the solution in sed/awk/perl. Thanks .. Input File a.txt: ================= 1 2 3 abcd 4 5 6 7 8 (7 Replies)
Discussion started by: manuswami
7 Replies

8. Shell Programming and Scripting

print lines with exact pattern match

I have in a file domain.com. 1909 IN A 1.22.33.44 domain.com. 1909 IN A 22.33.44.55 ns1.domain.com. 1699 IN A 33.44.55.66 ns2.domain.com. 1806 IN A 77.77.66.66 I need to "grep" or "awk" out the lines starting with domain.com. as follows. domain.com. 1909 IN A 1.22.33.44 domain.com.... (3 Replies)
Discussion started by: anilcliff
3 Replies

9. Shell Programming and Scripting

sed print all lines after pattern match

HiCan someone show me how to print all lines from a file after a line matching a pattern using sed?Thanks (13 Replies)
Discussion started by: steadyonabix
13 Replies

10. Shell Programming and Scripting

Perl script to match a pattern and print lines

Hi I have a file (say 'file1')and I want to search for a first occurence of pattern (say 'ERROR') and print ten lines in the file below pattern. I have to code it in PERL and I am using Solaris 5.9. I appreciate any help with code Thanks Ammu (6 Replies)
Discussion started by: ammu
6 Replies
Login or Register to Ask a Question