Login or Register to Ask a Question and Join Our Community


Shell Programming and Scripting

Extract two lines before and after the 'search text'

Login to Discuss or Reply to this Discussion in Our Community

 
Thread Tools Search this Thread
Top Forums Shell Programming and Scripting Extract two lines before and after the 'search text'
# 1  
Old 04-12-2010
Extract two lines before and after the 'search text'
Hi Guys,
I have a situation wherein I need to extract two lines from below the search string.

Eg.

Current:

Code:
 
$ grep "$(date +'%a %b %e')" alert.log
Mon Apr 12 03:58:10 2010
Mon Apr 12 12:51:48 2010
$

Here I would like the display to be something like

Code:
 
Mon Apr 12 12:51:48 2010
Thread 1 advanced to log sequence 1629 (LGWR switch)
Current log# 3 seq# 1629 mem# 0: /dborafiles/ipvpn/vpn/oraredo01/redo03.log

Please assist. Thank you.
# 2  
Old 04-12-2010
which OS?

try,
Code:
grep -A2 "$(date +'%a %b %e')" alert.log

for non GNU systems, an awk workaround,

Code:
awk 'c-->0;$0~s{if(b)for(c=b+1;c>1;c--)print r[(NR-c+1)%b];print;c=a}b{r[NR%b]=$0}' b=0 a=2 s="$(date +'%a %b %e')" alert.log

# 3  
Old 04-12-2010
Thanks Anchal, OS is SunOS.

---------- Post updated at 02:48 PM ---------- Previous update was at 02:45 PM ----------

Anchal,

the grep -A2 does not work on Sun OS.


about awk option, it gives me an error, are you able to help resolve this?

Code:
$ awk 'c-->0;$0~s{if(b)for(c=b+1;c>1;c--)print r[(NR-c+1)%b];print;c=a}b{r[NR%b]=$0}' b=0 a=2 s="$(date +'%a %b %e')" /dborafiles/ipvpn/vpn/admin/vpn/bdump/alert_vpn.log
awk: syntax error near line 1
awk: bailing out near line 1
$

# 4  
Old 04-12-2010
Try this:
Code:
awk '$0 ~ d {c=3} c-- > 0' d="$(date +'%a %b %e')" /dborafiles/ipvpn/vpn/admin/vpn/bdump/alert.log

Use nawk or /usr/xpg4/bin/awk on Solaris.
# 5  
Old 04-12-2010
Thank you Franklin, it worked ok for two lines below the search string...
For my information ... if I need two lines above the search string ...what would be the code?
# 6  
Old 04-12-2010
One way:
Code:
awk '$0 ~ d {print b;print a; print;exit}{b=a;a=$0}' d="$(date +'%a %b %e')" /dborafiles/ipvpn/vpn/admin/vpn/bdump/alert.log

# 7  
Old 04-12-2010
What about this:

Code:
awk '{line[NR]=$0; if ($0 ~ /d/) ind=NR}END{for(i=ind-2;i<=ind+2;i++)if(i != ind)print line[i]}' d="$(date +'%a %b %e')" file3

Last edited by devtakh; 04-12-2010 at 07:44 AM.. Reason: changed no of lines
Login or Register to Ask a Question

Previous Thread | Next Thread

10 More Discussions You Might Find Interesting

1. UNIX for Beginners Questions & Answers

How to search a text in file and retrieve required lines following it with UNIX command?

I have requirement to search for a text in the file and retrieve required lines that is user defined with unix command. Eg: Find the text UNIX in the below file and need to return Test 8 & Test 9 Test 1 Test 2 Test 3 Test 4 UNIX Test 5 Test 6 Test 7 Test 8 Test 9 Result can... (8 Replies)
Discussion started by: Arunkumarsak4
8 Replies

2. Shell Programming and Scripting

Extract lines from text files

I have some files containing the following data # RESIDUE AA STRUCTURE BP1 BP2 ACC N-H-->O O-->H-N N-H-->O O-->H-N TCO KAPPA ALPHA PHI PSI X-CA Y-CA Z-CA 1 196 A M 0 0 230 0, 0.0 2,-0.2 0, 0.0 0, 0.0 0.000 360.0 360.0 360.0 76.4 21.7 -6.8 11.3 2 197 A D + 0 0 175 1,-0.1 2,-0.1 0, 0.0 0, 0.0... (10 Replies)
Discussion started by: edweena
10 Replies

3. Shell Programming and Scripting

extract lines from text after keyword

I have a text and I want to extract the 4 lines following a keyword! For example if I have this text and the keyword is AAA hello helloo AAA one two three four helloooo hellooo I want the output to be one two three four (7 Replies)
Discussion started by: stekanius
7 Replies

4. Shell Programming and Scripting

Search for a pattern,extract value(s) from next line, extract lines having those extracted value(s)

I have hundreds of files to process. In each file I need to look for a pattern then extract value(s) from next line and then search for value(s) selected from point (2) in the same file at a specific position. HEADER ELECTRON TRANSPORT 18-MAR-98 1A7V TITLE CYTOCHROME... (7 Replies)
Discussion started by: AshwaniSharma09
7 Replies

5. UNIX for Dummies Questions & Answers

Help please, extract multiple lines from a text file

Hi all, I need to extract lines between the lines 'RD' and 'QA' from a text file (following). there are more that one of such pattern in the file and I need to extract all of them. however, the number of lines between them is varied in the file. Therefore, I can not just use 'grep -A' command.... (6 Replies)
Discussion started by: johnshembb
6 Replies

6. Shell Programming and Scripting

AWK: How to extract text lines between two strings

Hi. I have a text test1.txt file like:Receipt Line1 Line2 Line3 End Receipt Line4 Line5 Line6 Canceled Receipt Line7 Line8 Line9 End (9 Replies)
Discussion started by: TQ3
9 Replies

7. Shell Programming and Scripting

extract particular lines from text file

I have two files file A which have a number in every row and file B which contains few hundred thousand rows with about 300 characters in each row (csv) What I need is to extract whole rows from B file (only these which numbers are indicated in A file) I also need to use cygwin. Any... (7 Replies)
Discussion started by: gunio
7 Replies

8. Shell Programming and Scripting

Extract lines of text based on a specific keyword

I regularly extract lines of text from files based on the presence of a particular keyword; I place the extracted lines into another text file. This takes about 2 hours to complete using the "sort" command then Kate's find & highlight facility. I've been reading the forum & googling and can find... (4 Replies)
Discussion started by: DionDeVille
4 Replies

9. Shell Programming and Scripting

extract the lines between specific line number from a text file

Hi I want to extract certain text between two line numbers like 23234234324 and 54446655567567 How do I do this with a simple sed or awk command? Thank you. ---------- Post updated at 06:16 PM ---------- Previous update was at 05:55 PM ---------- found it: sed -n '#1,#2p'... (1 Reply)
Discussion started by: return_user
1 Replies

10. Shell Programming and Scripting

need to search text and output previous lines

I have a file (OMlog0) that is quite large, I need to find the line "Automatic Recharge Audit Process Finished" and output that line and the time stamp that occurs two lines previous. The line that I was using is "sed -n '/Automatic Recharge Audit Process Finished/,/No errors/p' /sn/log/OM* >... (8 Replies)
Discussion started by: grinds
8 Replies
Login or Register to Ask a Question