Sponsored Content
Full Discussion: read file backwards
Top Forums Shell Programming and Scripting read file backwards Post 302137957 by bluemoon1 on Thursday 27th of September 2007 11:33:47 PM
Old 09-28-2007
read file backwards

Assume file1 contains a list of strings.
My first script is scanning the file and deals with the lines with a certain patern in it:

grep 'somepatern' file1 \
while read LINE ; do
doSomethingAboutIt
done

Now, I need a second script that deals with the same lines (& do something differently) but in the opposite order; the last line found in the file with that patern shuld be handled first.

Please help me. Thanks so much!!!

Last edited by bluemoon1; 09-28-2007 at 12:36 AM.. Reason: typo
 

10 More Discussions You Might Find Interesting

1. AIX

ML level went backwards?

Hi all. I've been put in charge of updating one of our AIX 5.2 servers to ML7. (perhaps not wise since I'm an absolute n00b, but hey, it's good experience to fly by the seat of one's pants). So: a) I typed "oslevel -r" and got back "5200-04" b) I went to IBM's Fix Central and downloaded... (1 Reply)
Discussion started by: pschlesinger
1 Replies

2. UNIX for Advanced & Expert Users

Scanning file backwards

Is there any way to look for a directory path that is listed any number of lines *before* a keyword in an error message? I have a script that is trying to process different files that are always down a certain portion of a path, and if there is an error, then says there is an error, contact... (2 Replies)
Discussion started by: tekster757
2 Replies

3. 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

4. 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

5. 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

6. Shell Programming and Scripting

Searching backwards using regular expressions

I'm having trouble writing a regular expression that matches the text I need it to. Let me give an example to express my trouble. Suppose I have the following text: if(condition) multiline statement else if(condition) multiline statement else if(condition) multiline statement else... (3 Replies)
Discussion started by: Altay_H
3 Replies

7. Shell Programming and Scripting

Backwards question mark appearing in FTP'd file

Hi all, I'm trying to FTP what looks like a simple .txt file from my Windows XP desktop to my UNIX server. I've tried using several programs to do this including UltraEdit and FTP Commander. I have tried sending it ascii, binary and even let the program decide. But every time it arrives in UNIX... (4 Replies)
Discussion started by: Korn0474
4 Replies

8. 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

9. 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

10. Shell Programming and Scripting

Match text to lines in a file, iterate backwards until text or text substring matches, print to file

hi all, trying this using shell/bash with sed/awk/grep I have two files, one containing one column, the other containing multiple columns (comma delimited). file1.txt abc12345 def12345 ghi54321 ... file2.txt abc1,text1,texta abc,text2,textb def123,text3,textc gh,text4,textd... (6 Replies)
Discussion started by: shogun1970
6 Replies
merge(1)																  merge(1)

NAME
merge - three-way file merge SYNOPSIS
merge [-Llabel1 [-Llabel3]] [-p] [-q] file1 file2 file3 DESCRIPTION
merge incorporates all changes that lead from file2 to file3 into file1. The result goes to standard output if -p is present, into file1 otherwise. merge is useful for combining separate changes to an original. Suppose file2 is the original, and both file1 and file3 are modifications of file2. Then merge combines both changes. An overlap occurs if both file1 and file3 have changes in a common segment of lines. On a few older hosts where diff3 does not support the -E option, merge does not detect overlaps, and merely supplies the changed lines from file3. On most hosts, if overlaps occur, merge out- puts a message (unless the -q option is given), and includes both alternatives in the result. The alternatives are delimited as follows: <<<<<<< file1 lines in file1 ======= lines in file3 >>>>>>> file3 If there are overlaps, the user should edit the result and delete one of the alternatives. If the -L label1 and -L label3 options are given, the labels are output in place of the names file1 and file3 in overlap reports. DIAGNOSTICS
Exit status is 0 for no overlaps, 1 for some overlaps, 2 for trouble. IDENTIFICATION
Author: Walter F. Tichy. Revision Number: 1.1.6.2; Release Date: 1993/10/07. Copyright (C) 1982, 1988, 1989 by Walter F. Tichy. Copyright (C) 1990, 1991 by Paul Eggert. SEE ALSO
diff3(1), diff(1), rcsmerge(1), co(1) merge(1)
All times are GMT -4. The time now is 07:55 AM.
Unix & Linux Forums Content Copyright 1993-2022. All Rights Reserved.
Privacy Policy