Sponsored Content
Top Forums Shell Programming and Scripting extract a line from a file using the line number Post 302082653 by System Shock on Wednesday 2nd of August 2006 10:21:08 PM
Old 08-02-2006
If you want a particular line number, say line 4, using head and tail commands:
Code:
 head -4 filename | tail -1

Using sed:
Code:
 sed 4!d filename

 

10 More Discussions You Might Find Interesting

1. Shell Programming and Scripting

Extract a line from a file using the line number

I have a shell script and want to assign a value to a variable. The value is the line exctrated from a file using the line number. The line number it is not fix, and could change any time. I have tried sed, awk, head .. See my script # Get randome line number from the file #selectedline = `awk... (1 Reply)
Discussion started by: zambo
1 Replies

2. Shell Programming and Scripting

how to get the data from line number 1 to line number 100 of a file

Hi Everybody, I am trying to write a script that will get some perticuler data from a file and redirect to a file. My Question is, I have a Very huge file,In that file I have my required data is started from 25th line and it will ends in 100th line. I know the line numbers, I need to get all... (9 Replies)
Discussion started by: Anji
9 Replies

3. 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

4. UNIX for Dummies Questions & Answers

How to read contents of a file from a given line number upto line number again specified by user

Hello Everyone. I am trying to display contains of a file from a specific line to a specific line(let say, from line number 3 to line number 5). For this I got the shell script as shown below: if ; then if ; then tail +$1 $3 | head -n $2 else ... (5 Replies)
Discussion started by: grc
5 Replies

5. Shell Programming and Scripting

get the fifth line of a text file into a shell script and trim the line to extract a WORD

FOLKS , i have a text file that is generated automatically of an another korn shell script, i want to bring in the fifth line of the text file in to my korn shell script and look for a particular word in the line . Can you all share some thoughts on this one. thanks... Venu (3 Replies)
Discussion started by: venu
3 Replies

6. Shell Programming and Scripting

Extract a number from a line in a file and sed in another copied file

Dear all, I am trying to extract a number from a line in one file (task 1), duplicate another file (task 2) and replace all instances of the strings 300, in duplicated with the extracted number (task 3). Here is what I have tried so far: for ((k=1;k<4;k++)); do temp=`sed -n "${k}p"... (2 Replies)
Discussion started by: mnaqvi
2 Replies

7. Shell Programming and Scripting

Extract string from multiple file based on line count number

Hi, I search all forum, but I can not find solutions of my problem :( I have multiple files (5000 files), inside there is this data : FILE 1: 1195.921 -898.995 0.750312E-02-0.497526E-02 0.195382E-05 0.609417E-05 -2021.287 1305.479-0.819754E-02 0.107572E-01 0.313018E-05 0.885066E-05 ... (15 Replies)
Discussion started by: guns
15 Replies

8. Shell Programming and Scripting

extract a line from a file by line number

Hi guys, does anyone know how to extract(grep) a line from the file, if I know the line number? Thanks a lot. (9 Replies)
Discussion started by: aoussenko
9 Replies

9. Shell Programming and Scripting

HELP: Shell Script to read a Log file line by line and extract Info based on KEYWORDS matching

I have a LOG file which looks like this Import started at: Mon Jul 23 02:13:01 EDT 2012 Initialization completed in 2.146 seconds. -------------------------------------------------------------------------------- -- Import summary for Import item: PolicyInformation... (8 Replies)
Discussion started by: biztank
8 Replies

10. Shell Programming and Scripting

Perl to extract information from a file line by line

In the below perl code I am using tags within each line to extract certain information. The tags that are used are: STB >0.8 is STRAND BIAS otherwise GOOD FDP is the second number GO towards the end of the line is read into an array and the value returned is outputed, in the first line that... (1 Reply)
Discussion started by: cmccabe
1 Replies
TAIL(1) 						    BSD General Commands Manual 						   TAIL(1)

NAME
tail -- display the last part of a file SYNOPSIS
tail [-F | -f | -r] [-b number | -c number | -n number] [file ...] DESCRIPTION
The tail utility displays the contents of file or, by default, its standard input, to the standard output. The display begins at a byte, line or 512-byte block location in the input. Numbers having a leading plus (``+'') sign are relative to the beginning of the input, for example, ``-c +2'' starts the display at the second byte of the input. Numbers having a leading minus (``-'') sign or no explicit sign are relative to the end of the input, for example, ``-n 2'' displays the last two lines of the input. The default starting location is ``-n 10'', or the last 10 lines of the input. The options are as follows: -b number The location is number 512-byte blocks. -c number The location is number bytes. -f The -f option causes tail to not stop when end of file is reached, but rather to wait for additional data to be appended to the input. The -f option is ignored if the standard input is a pipe, but not if it is a FIFO. -F The -F option implies the -f option, but tail will also check to see if the file being followed has been renamed or rotated. The file is closed and reopened when tail detects that the filename being read from has a new inode number. The -F option is ignored if reading from standard input rather than a file. -n number The location is number lines. -r The -r option causes the input to be displayed in reverse order, by line. Additionally, this option changes the meaning of the -b, -c and -n options. When the -r option is specified, these options specify the number of bytes, lines or 512-byte blocks to display, instead of the bytes, lines or blocks from the beginning or end of the input from which to begin the display. The default for the -r option is to display all of the input. If more than a single file is specified, each file is preceded by a header consisting of the string ``==> XXX <=='' where ``XXX'' is the name of the file. DIAGNOSTICS
The tail utility exits 0 on success, and >0 if an error occurs. SEE ALSO
cat(1), head(1), sed(1) STANDARDS
The tail utility is expected to be a superset of the IEEE Std 1003.2-1992 (``POSIX.2'') specification. In particular, the -F, -b and -r options are extensions to that standard. The historic command line syntax of tail is supported by this implementation. The only difference between this implementation and historic versions of tail, once the command line syntax translation has been done, is that the -b, -c and -n options modify the -r option, i.e. ``-r -c 4'' displays the last 4 characters of the last line of the input, while the historic tail (using the historic syntax ``-4cr'') would ignore the -c option and display the last 4 lines of the input. HISTORY
A tail command appeared in PWB UNIX. BSD
June 6, 1993 BSD
All times are GMT -4. The time now is 06:21 PM.
Unix & Linux Forums Content Copyright 1993-2022. All Rights Reserved.
Privacy Policy