how to remove specific lines from a file


 
Thread Tools Search this Thread
Top Forums Shell Programming and Scripting how to remove specific lines from a file
# 8  
Old 09-29-2007
Code:
awk 'no&&/str/{next};/The F/{no=1;next}1' filename

# 9  
Old 10-01-2007
Thanks all for your response!!

radoulov: it doesn't seem to work on Solaris (syntax error)

aigles: is it bourne-shell? I'm still trying to get it to work on Solaris (syntax error)
# 10  
Old 10-02-2007
Try with nawk instead of awk

Jean-Pierre.
# 11  
Old 10-04-2007
Quote:
Originally Posted by varungupta
Hey,

To delete a line where a pattern matches, you can use sed.

sed '/^[Mm]ango/d' file1.txt

Above command will delete all the lines which starts with the word Mango or mango.

Smilie
Can we add a line which starts with the word Mango (or any partten in the middle of the line) only the line does not exist in the file already?
I can do a grep and check the existance & then use echo to append the line.... is there a one line command like the above? ;-)

Thanks in advance for your reply!!
# 12  
Old 10-04-2007
Try...
Code:
grep -q Mango file1.txt || echo Mango >> file1.txt

# 13  
Old 10-05-2007
Guru Ygor/aigles/radoulov/varungupta/porter/summer_cherry;-)

Thank you all for your advice. Very helpful!!

Nikki
# 14  
Old 10-05-2007
Quote:
Originally Posted by radoulov
Code:
nawk 'no&&/str/{next};/The F/{no=1;next}1' filename

As my home work, I tried to figure it out how it works (though I know it works) but still no luck:-( Would someone elabrate a little of the syntax for me? Many thanks in advance!
Login or Register to Ask a Question

Previous Thread | Next Thread

10 More Discussions You Might Find Interesting

1. UNIX for Beginners Questions & Answers

awk with sed to combine lines and remove specific odd # pattern from line

In the awk piped to sed below I am trying to format file by removing the odd xxxx_digits and whitespace after, then move the even xxxx_digit to the line above it and add a space between them. There may be multiple lines in file but they are in the same format. The Filename_ID line is the last line... (4 Replies)
Discussion started by: cmccabe
4 Replies

2. Shell Programming and Scripting

Remove duplicate consecutive lines with specific string

Hello, I'm trying to remove the duplicate consecutive lines with specific string "WARNING". File.txt abc; WARNING 2345 WARNING 2345 WARNING 2345 WARNING 2345 WARNING 2345 bcd; abc; 123 123 123 WARNING 1234 WARNING 2345 WARNING 2345 efgh; (6 Replies)
Discussion started by: Mannu2525
6 Replies

3. Shell Programming and Scripting

Remove lines matching a substring in a specific column

Dear group, I have following input text file: Brit 2016 11 18 12 00 10 1.485,00 EUR Brit 2016 11 18 12 00 10 142,64 EUR Brit 2016 11 18 12 00 10 19,80 EUR Brit 2016 11 18 12 00 10 545,00 EUR Brit 2016 11 18 12 00 10 6.450,00 EUR... (3 Replies)
Discussion started by: gfhsd
3 Replies

4. Shell Programming and Scripting

awk to remove lines in file if specific field matches

I am trying to remove lines in the target.txt file if $5 before the - in that file matches sorted_list. I have tried grep and awk. Thank you :). grep grep -v -F -f targets.bed sort_list grep -vFf sort_list targets awk awk -F, ' > FILENAME == ARGV {to_remove=1; next} > ! ($5 in... (2 Replies)
Discussion started by: cmccabe
2 Replies

5. Shell Programming and Scripting

NAWK to remove lines that matches a specific pattern

Hi, I have requirement that I need to split my input file into two files based on a search pattern "abc" For eg. my input file has below content abc defgh zyx I need file 1 with abc and file2 with defgh zyx I can use grep command to acheive this. But with grep I need... (8 Replies)
Discussion started by: sbhuvana20
8 Replies

6. Shell Programming and Scripting

Sed or Awk to remove specific lines

I have searched the forum for this - forgive me if I missed a previous post. I have the following file: blah blah blah blah blah blah blah blah blah blah blah blah blah blah blah alter table "informix".esc_acct add constraint (foreign key (fi_id) references "informix".fi ... (5 Replies)
Discussion started by: Shoeless_Mike
5 Replies

7. Shell Programming and Scripting

how to remove specific lines from a file (reprise)

Hello, I've to change the shell in /etc/passwd for some users . I've the list of users but I'm not able to modify the file with scripting . I'm working on a Sol10 . Can anyone help me ? tnks (7 Replies)
Discussion started by: gogol_bordello
7 Replies

8. Shell Programming and Scripting

How to remove the specific lines from file using perl

Can anyone tell me what could be the solution to following : I have one .txt file which contains some "seed" information. This seed may appear multiple time in the file so what I want do is if this seed appears again in the file then that line should be removed. Please provide the script code... (4 Replies)
Discussion started by: dipakg
4 Replies

9. Shell Programming and Scripting

remove specific lines from flat file using perl

Hi, Here is wat im looking for.. i have a flat file which looks like this.. 00 * * * * .. .. * * text text text COL1 COL2 ----- ----- 1 a (12 Replies)
Discussion started by: meghana
12 Replies

10. Shell Programming and Scripting

remove specific lines from a file

Hi there I have a file with a variable amount of rows but the 45th, 46th and 47th charachter of each line is the status field which is a three digit code ie 001, 002, 003 etc. My question is this..I need to strip all the records/lines with 002's out of the file completely and put them into... (14 Replies)
Discussion started by: hcclnoodles
14 Replies
Login or Register to Ask a Question