Login or Register to Ask a Question and Join Our Community


Shell Programming and Scripting

search backwards relative to a string

Login to Discuss or Reply to this Discussion in Our Community

 
Thread Tools Search this Thread
Top Forums Shell Programming and Scripting search backwards relative to a string
# 1  
Old 10-22-2008
Bug search backwards relative to a string
Hi,

I have to search for first occurenceof string str1 in a file(>5GB).

Now, after I have that , I have to search backwards from that offset till I get another string str2. I should also be able to get the
new string str2's offset.

Similarly, I look for last occurence of str1 and then have to search forward from there for str2 and get its offset .

First occurence :--
grep str1 file | head -1

Last occurence :--
grep str1 file | tail -1

But, I dont know how to do relative search in backward & forward directions, so that I have their offsets ..??

Please help...

finder
Last edited by finder255; 10-22-2008 at 05:22 PM..
# 2  
Old 10-22-2008
Hammer & Screwdriver Here are a couple commands to think about
cat -n will display a file with line number
tac will display a file in reverse order

These two commands, and in combination with other commands, should be able to get you on your way. Try to write something, then come back if still issues.
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 use a grep search to search for a specific string within multiple directories?

Lets say I have a massive directory which is filled with other directories all filled with different c++ scripts and I want a listing of all the scripts that contain the string: "this string". Is there a way to use a grep search for that? I tried: grep -lr "this string" * but I do not... (3 Replies)
Discussion started by: Circuits
3 Replies

2. Shell Programming and Scripting

Sed: find and replace backwards, until string

Some help please: Need to find string ||(everything in front of it)B0300|| and replace it with ||0|| globally In: 16112121||||0||0||0||0||0||52||52||0||0||0||0||1507200053342B0300||1507200053342B0300||0||0||0||0700 Out: 16112121||||0||0||0||0||0||52||52||0||0||0||0||0||0||0||0||0||0700 ... (4 Replies)
Discussion started by: drbiloukos
4 Replies

3. Shell Programming and Scripting

Search string within a file and list common words from the line having the search string

Hi, Need your help for this scripting issue I have. I am not really good at this, so seeking your help. I have a file looking similar to this: Hello, i am human and name=ABCD. How are you? Hello, i am human and name=PQRS. I am good. Hello, i am human and name=ABCD. Good bye. Hello, i... (12 Replies)
Discussion started by: royzlife
12 Replies

4. Shell Programming and Scripting

Search several string and convert into a single line for each search string using awk command AIX?.

I need to search the file using strings "Request Type" , " Request Method" , "Response Type" and by using result set find the xml tags and convert into a single line?. below are the scenarios. Cat test Nov 10, 2012 5:17:53 AM INFO: Request Type Line 1.... (5 Replies)
Discussion started by: laknar
5 Replies

5. Shell Programming and Scripting

Search backwards to certain string

Hi, I'm using the following to do a backwards search of a file for a string sed s/^M//g FILE | nawk 'c-->0;$0~s{if(b)for(c=b+1;c>1;c--)print r;print;c=a}b{r=$0}' b=10 a=0 s="9005"|grep "policy "|sort -u |awk '{print $4}'|cut -c2-10 My issue is that because I'm looking back 10 lines it's... (11 Replies)
Discussion started by: SaltyDog
11 Replies

6. Programming

How to search a file based on a time stamp backwards 10 seconds

Hi all, I'm after some help with this small issue which i'm struggling to work out a fix for. I have a file that contains records that all have a time stamp for each individual record, i need to search the file for a specific time stamp and then search back 10 seconds to see if the number... (2 Replies)
Discussion started by: sp3arsy
2 Replies

7. Shell Programming and Scripting

search for string and replace backwards

I'm new to Unix scripting and I'm not sure if this can be done. Example: search (grep) in a file for 'Control ID' and then replace with 4 blanks 7 bytes before 'Control ID. input "xxxxxx1234xxxxxxxControl IDxxxxxx" output: "xxxxxx xxxxxxxControl IDxxxxxx" thanks! (7 Replies)
Discussion started by: jbt828
7 Replies

8. Shell Programming and Scripting

How to search backwards in a log file by timestamp of entries?

Hello. I'm not nearly good enough with awk/perl to create the logfile scraping script that my boss is insisting we need immediately. Here is a brief 3-line excerpt from the access.log file in question (actual URL domain changed to 'aaa.com'): 209.253.130.36 - - "GET... (2 Replies)
Discussion started by: kevinmccallum
2 Replies

9. Shell Programming and Scripting

Search backwards

Hi, I have a variable , lets say a=/disk1/net/first.ksh i need to grep "first.ksh" everytime "a" gets changed dynamically and i do not know how many '"/" are there in my variable. Can somebody help me out. (9 Replies)
Discussion started by: giri_luck
9 Replies

10. UNIX for Dummies Questions & Answers

get cygpath to leave relative paths as relative?

If I execute mypath=`cygpath -w ../` echo $mypath I get d:\unix\nextVersion\script OK, d:\unix\nextVersion\script is the correct windows version of the path, but it is in absolute form. I would prefer it if cygpath left it in relative form, i.e. echo $mypath should output ..\ ... (0 Replies)
Discussion started by: fabulous2
0 Replies
Login or Register to Ask a Question