Login or Register to Ask a Question and Join Our Community

Sponsored Content
Full Discussion: Delete first 100 lines from a BIG File
Top Forums UNIX for Advanced & Expert Users Delete first 100 lines from a BIG File Post 302659365 by methyl on Wednesday 20th of June 2012 07:27:33 PM
Old 06-20-2012
IMHO @drl's solution in post #15 nearly fulfils the requirement.

Reading between the lines, we are again presented with a faulty solution without a definition of the actual problem.

Taking into account Corona688's comment about inodes, this code would be safer on most unix/Linux Operating Systems:
Code:
cp test.log back.log
sed '1,100d' test.log>temp.log 
cat temp.log > test.log


I have used a similar code construct (albeit with grep -v)to remove persistent irrelevant entries from a system log where it was causing unwanted alerts (pending a fix).
Last edited by methyl; 06-20-2012 at 08:55 PM..
This User Gave Thanks to methyl For This Post:
unohu
 

10 More Discussions You Might Find Interesting

1. Solaris

delete first 100 lines rather than zero out of file

Hi experts, in my solaris 9 the file- /var/adm/messeages growin too first. by 24 hours 40MB. And always giving the below messages-- bash-2.05# tail -f messages Nov 9 16:35:38 ME1 last message repeated 1 time Nov 9 16:35:38 ME1 ftpd: wtmpx /var/adm/wtmpx No such file or directory Nov 9... (7 Replies)
Discussion started by: thepurple
7 Replies

2. Solaris

delete first 100 lines from a file

I have a file with 28,00,000 lines of rows in this the first 80 lines will be chunks . I want to delete the chunks of 80 lines. I tried tail -f2799920 filename. is there any efficient way to do this. Thanks in advance. (7 Replies)
Discussion started by: salaathi
7 Replies

3. Shell Programming and Scripting

How to delete lines in a file that have duplicates or derive the lines that aper once

Input: a b b c d d I need: a c I know how to get this (the lines that have duplicates) : b d sort file | uniq -d But i need opossite of this. I have searched the forum and other places as well, but have found solution for everything except this variant of the problem. (3 Replies)
Discussion started by: necroman08
3 Replies

4. Shell Programming and Scripting

Print #of lines after search string in a big file

I have a command which prints #lines after and before the search string in the huge file nawk 'c-->0;$0~s{if(b)for(c=b+1;c>1;c--)print r;print;c=a}b{r=$0}' b=0 a=10 s="STRING1" FILE The file is 5 gig big. It works great and prints 10 lines after the lines which contains search string in... (8 Replies)
Discussion started by: prash184u
8 Replies

5. Shell Programming and Scripting

Re: Deleting lines from big file.

Hi, I have a big (2.7 GB) text file. Each lines has '|' saperator to saperate each columns. I want to delete those lines which has text like '|0|0|0|0|0' I tried: sed '/|0|0|0|0|0/d' test.txt Unfortunately, it scans the file but does nothing. file content sample:... (4 Replies)
Discussion started by: dipeshvshah
4 Replies

6. UNIX for Advanced & Expert Users

In a huge file, Delete duplicate lines leaving unique lines

Hi All, I have a very huge file (4GB) which has duplicate lines. I want to delete duplicate lines leaving unique lines. Sort, uniq, awk '!x++' are not working as its running out of buffer space. I dont know if this works : I want to read each line of the File in a For Loop, and want to... (16 Replies)
Discussion started by: krishnix
16 Replies

7. Shell Programming and Scripting

Delete rows from big file

Hi all, I have a big file (about 6 millions rows) and I have to delete same occurrences, stored in a small file (about 9000 rews). I have tried this: while read line do grep -v $line big_file > ok_file.tmp mv ok_file.tmp big_file done < small_file It works, but is very slow. How... (2 Replies)
Discussion started by: Tibbeche
2 Replies

8. UNIX for Dummies Questions & Answers

Delete records from a big file based on some condition

Hi, To load a big file in a table,I have a make sure that all rows in the file has same number of the columns . So in my file if I am getting any rows which have columns not equal to 6 , I need to delete it . Delimiter is space and columns are optionally enclosed by "". This can be ... (1 Reply)
Discussion started by: hemantraijain
1 Replies

9. Shell Programming and Scripting

Want to extract certain lines from big file

Hi All, I am trying to get some lines from a file i did it with while-do-loop. since the files are huge it is taking much time. now i want to make it faster. The requirement is the file will be having 1 million lines. The format is like below. ##transaction, , , ,blah, blah... (38 Replies)
Discussion started by: mad man
38 Replies

10. UNIX for Beginners Questions & Answers

How to copy only some lines from very big file?

Dear all, I have stuck with this problem for some days. I have a very big file, this file can not open by vi command. There are 200 loops in this file, in each loop will have one line like this: GWA quasiparticle energy with Z factor (eV) And I need 98 lines next after this line. Is... (6 Replies)
Discussion started by: phamnu
6 Replies

LEARN ABOUT DEBIAN

sdr2file

SDR2FILE(1)							  ICI executables						       SDR2FILE(1)

NAME

       sdr2file - SDR data extraction test program

SYNOPSIS

       sdr2file configFlags

DESCRIPTION

       sdr2file stress-tests SDR data extraction by retrieving and deleting all text file lines inserted into a test SDR data store named
       "testsdrconfigFlags" by the complementary test program file2sdr(1).

       The operation of sdr2file echoes the cyclical operation of file2sdr: each linked list created by file2sdr is used to create in the current
       working directory a copy of file2sdr's original source text file.  The name of each file written by sdr2file is file_copy_cycleNbr, where
       cycleNbr identifies the linked list from which the file's text lines were obtained.

       sdr2file may catch up with the data ingestion activity of file2sdr, in which case it blocks (taking the file2sdr test semaphore) until the
       linked list it is currently draining is no longer empty.

EXIT STATUS

       0   sdr2file has terminated.

FILES

       No configuration files are needed.

ENVIRONMENT

       No environment variables apply.

DIAGNOSTICS

       Can't use sdr.
	   ION system error.  Check for diagnostics in the ION log file ion.log.

       Can't create semaphore.
	   ION system error.  Check for diagnostics in the ION log file ion.log.

       SDR transaction failed.
	   ION system error.  Check for diagnostics in the ION log file ion.log.

       Can't open output file
	   Operating system error.  Check errtext, correct problem, and rerun.

       can't write to output file
	   Operating system error.  Check errtext, correct problem, and rerun.

BUGS

       Report bugs to <ion-bugs@korgano.eecs.ohiou.edu>

SEE ALSO

       file2sdr(1), sdr(3)

perl v5.14.2							    2012-05-25							       SDR2FILE(1)
All times are GMT -4. The time now is 11:24 AM.
Unix & Linux Forums Content Copyright 1993-2022. All Rights Reserved.
Privacy Policy