Sponsored Content
Top Forums UNIX for Dummies Questions & Answers Line deletion help using perl -ne Post 302154905 by lijju.mathew on Wednesday 2nd of January 2008 11:49:35 AM
Old 01-02-2008
Line deletion help using perl -ne

Hi all,

I know the one liner to delete all the lines in a file which matches a pattern
i.e

perl -i.old -ne 'print unless /pattern/' file

Now i need the perl onliner to delete all the lines which doesnt match the pattern. Also what is the difference between perl -i and perl -i.old.
Does perl -i.old archive the existing file?

Your help in this will be appreciated.

Thanks in advance.

Lijju
 

10 More Discussions You Might Find Interesting

1. Shell Programming and Scripting

Multiple Files deletion in perl

Hello Friends, I want to delete all the "*.trg" files in a directory but i don't want to do it by system("rm -r *.trg"); Can i do it thru unlink or by any other mean Thanks, Pulkit (1 Reply)
Discussion started by: pulkit
1 Replies

2. Shell Programming and Scripting

blank line deletion in a file using perl

Dear All, I am looking for an option in perl using which i could delete empty lines in a file. Or the alternative of sed '/^$/d' <filename> in perl. Sed is not working in my perl script :( Pls help me out . Thanks, VG (4 Replies)
Discussion started by: vguleria
4 Replies

3. Shell Programming and Scripting

How to use Perl to merge multi-line into single line

Hi, Can anyone know how to use perl to merge the following multi-line information which beginning with "BAM" into one line. For each line need to delete the return and add a space. Please see the red color line. ******Org. Multi-line) BAM admin 101.203.57.22 ... (3 Replies)
Discussion started by: happyday
3 Replies

4. Shell Programming and Scripting

How to use Perl to join multi-line into single line

Hello, Did anyone know how to write a perl script to merge the multi-line into a single line where each line with start at timestamp Input--> timestamp=2009-11-10-04.55.20.829347; a; b; c; timestamp=2009-11-10-04.55.20.829347; aa; bb; cc; (5 Replies)
Discussion started by: happyday
5 Replies

5. Shell Programming and Scripting

Deletion of characters in every second line

Hi, I have a file with four types of lines: @HWUSI-EAS656_0022:8:1:175:376#0/1 CTCGACACGCTGGTGGAGATCCTCGGCCTGACCGAGGACGACCGGGCCATCTTCGAGCAGCGC + BBBBBBBA?AABB;<=B9<===AA1AA==>99===.9?:9A4A956%%%%%%%%%%%%%%%%% I want to remove the first 6 characters of every second line. This means in... (10 Replies)
Discussion started by: s052866
10 Replies

6. Shell Programming and Scripting

perl/unix: script in command line works but not in perl

so in unix this command works works and shows me a list of directories find . -name \*.xls -exec dirname {} \; | sort -u | > list.txt but when i try running a perl script to run this command my $query = 'find . -name \*.xls -exec dirname {} \; | sort -u | > list.txt';... (2 Replies)
Discussion started by: kpddong
2 Replies

7. Shell Programming and Scripting

PERL or SHELL Scrript to search in Directories by taking line by line from a text file

Unix box server version *********** >uname -r B.11.00 >echo $SHELL /usr/bin/ksh --> in this server, I have the path like /IMbuild/dev/im0serv1 ---> in that directory I have the folders startup(.jsp files nearly 100 jsp's ) and scripts(contains .js files nearly 100 files) ... (9 Replies)
Discussion started by: pasam
9 Replies

8. UNIX for Dummies Questions & Answers

sed - combination of line deletion and pattern matching

I want to delete all the blank lines from a file before a certain line number. e.g. Input file (n: denotes line number) 1: a 2: 3: b 4: c 5: 6: d I want to delete all blank lines before line number 3, such that my output is: a b c d I see that sed '/^$/d' in_file works... (9 Replies)
Discussion started by: jawsnnn
9 Replies

9. Shell Programming and Scripting

Make Multile line is one line using window Perl

Hi All I have a .csv file which is showing data as ESP Client,ESP Engagement,Misc_Projects_120101,DEFAULT,HA,Unknown,No,Unknown,201704,4.1,Unknown,AAA,Collected-Done,"she,joy.",200111,Unknown,Full Time,,Delivery_DONE AMO,Approved,2012-12-03,2012-12-06,2012-12-06,"Occupied Hours ... (7 Replies)
Discussion started by: adisky123
7 Replies

10. Shell Programming and Scripting

Perl command line option '-n','-p' and multiple files: can it know a file name of a printed line?

I am looking for help in processing of those options: '-n' or '-p' I understand what they do and how to use them. But, I would like to use them with more than one file (and without any shell-loop; loading the 'perl' once.) I did try it and -n works on 2 files. Question is: - is it possible to... (6 Replies)
Discussion started by: alex_5161
6 Replies
EvmEventNameMatch(3)					     Library Functions Manual					      EvmEventNameMatch(3)

NAME
EvmEventNameMatch(), EvmEventNameMatchStr() - match EVM event name SYNOPSIS
Library EVM Support Library Parameters pattern The event name pattern sought. The pattern may be any valid event name string. It may include wildcard characters in place of any component. event The event containing the event name to be compared against the pattern. match The result of the match. This operand is set to if the name matches the pattern, and to if it does not. candidate A character string to be matched against the pattern DESCRIPTION
Because special matching rules apply when deciding whether a candidate event name matches a known name, the EVM name matching functions should be used for matching purposes, rather than the C string comparison functions The EVM functions match an event name against a sup- plied pattern, ignoring any trailing appended components in the candidate name, and correctly matching wildcard characters. The function takes an event and an event name pattern as input, and returns an indication of whether the event contains a name which matches the pattern in the match output argument. The pattern may be any valid event name string, and may also include wildcard characters in place of any component. A wildcard in the pattern matches zero or more name components. A matches exactly one component. A match occurs if the event name matches all components indicated by the pattern, even if the name has additional trailing elements. The function performs the same check as but takes a character string as the candidate event name, instead of extracting the candidate event name from a supplied event. Both functions set the match output argument to if the name matches the pattern, and to if it does not. RETURN VALUE
The operation completed without error. The comparison was successful. The value of the match operand indicates whether the name matches the pattern. One of the arguments to the function is invalid. The supplied pattern contains invalid characters. The supplied event does not contain a name. ERRORS
The value of is not set. SEE ALSO
Routines memccpy(3C), strcat(3C). Event Management EVM(5). EVM Events EvmEvent(5). EvmEventNameMatch(3)
All times are GMT -4. The time now is 02:14 PM.
Unix & Linux Forums Content Copyright 1993-2022. All Rights Reserved.
Privacy Policy