Login or Register to Ask a Question and Join Our Community

Sponsored Content
Full Discussion: if match found go to a particular line in perl
Top Forums Shell Programming and Scripting if match found go to a particular line in perl Post 302180184 by user_prady on Sunday 30th of March 2008 09:47:35 AM
Old 03-30-2008
Quote:
Originally Posted by era
Don't depend on me, I need to be going back to my day job soon.

There's a number of ways to do this, obviously. The old-fashioned variant would be to remember the previous line and print that when you see the terminator. The really brute Perl approach would be to slurp the whole file and substitute everything with an empty string except the line before the terminator. There's one in the Perl FAQ about that; perlfaq6 and scroll around for related questions. (The question about C comments further down the page has some hints, too.)

But the "previous line" solution is absolutely the simplest in this case, if you have no further requirements.

Code:
perl -ne 'BEGIN { $matching = 0; }
  $matching = 1 if (m/^\*Main Start/);
  next unless $matching;
  print $prev if (defined $prev && m/^\*Main End/);
  $prev = $_'

Not sure about the flow control you tried to describe. Are you supposed to remember everything from main start until main end and print that after the output from the last line before main end? (I guess this already qualifies as a pseudo-code implementation of what it takes. But then maybe I would consider a regex substitution over the whole file, or each *Main Start section, after all.)
Thanks a Lot Era for your kindness..I ll try your mentioned way..
 

10 More Discussions You Might Find Interesting

1. Shell Programming and Scripting

Perl: Match a line with multiple search patterns

Hi I'm not very good with the serach patterns and I'd need a sample how to find a line that has multiple patterns. Say I want to find a line that has "abd", "123" and "QWERTY" and there can be any characters or numbers between the serach patterns, I have a file that has thousands of lines and... (10 Replies)
Discussion started by: Juha
10 Replies

2. Shell Programming and Scripting

help with script to send email and if subject line match is found

Help with script that will check log, then find a match is found, add that as the subject line. 1. The script will always run as a deamon.. and scan the event.log file 2. when a new 101 line is added to the event.log file, have the script check position 5,6 and 7 which is the job name, which... (2 Replies)
Discussion started by: axdelg
2 Replies

3. UNIX for Dummies Questions & Answers

awk display the match and 2 lines after the match is found.

Hello, can someone help me how to find a word and 2 lines after it and then send the output to another file. For example, here is myfile1.txt. I want to search for "Error" and 2 lines below it and send it to myfile2.txt I tried with grep -A but it's not supported on my system. I tried with awk,... (4 Replies)
Discussion started by: eurouno
4 Replies

4. UNIX for Dummies Questions & Answers

Display n lines after match found and other line

I have a file like this DoctorName Address1 Address2 DOB InsuredName Address1 Address2 DOB PatientName Address1 Address2 DOB ClaimNo1 DoctorName Address1 Address2 DOB InsuredName (2 Replies)
Discussion started by: nsuresh316
2 Replies

5. Shell Programming and Scripting

Displaying text till pattern match found in a line

Hi All, From the below line if we want to display all the text till found pattern dot/. I was trying with the below code but couldn't able to print text before the pattern. it display texts which is found after pattern. awk '/assed/{print;getline;print}' file_name | sed 's/^*. *//' input... (4 Replies)
Discussion started by: Optimus81
4 Replies

6. Shell Programming and Scripting

How to print the entire line if the mentioned match is found?

Hello Everyone, I have a file with 5 fields in each line just like mentioned below. Also the 4th field is time elapsed(hh:mm:ss) since the process is running xyz abc status 23:00:00 idle abc def status 24:00:00 idle def gji status 27:00:02 idle fgh gty status 00:00:00 idle Here I... (8 Replies)
Discussion started by: rahul2662
8 Replies

7. Shell Programming and Scripting

Perl removing line match with pattern in column

Hi, I have log like this: ... (1 Reply)
Discussion started by: justbow
1 Replies

8. Shell Programming and Scripting

Perl removing line match with pattern in column

Hi, I have log like this: ... (1 Reply)
Discussion started by: justbow
1 Replies

9. Shell Programming and Scripting

Add comment on last line if found match

Hi All, totally new on it , normally use it for just 1 line. i'm looking for help. i'm have 2 file. file 1 : -------------------------------------------------- c12 c1 c3 -------------------------------------------------- file 2: other content ... (10 Replies)
Discussion started by: kttan
10 Replies

10. UNIX for Beginners Questions & Answers

Modify text file if found multiple pattern match for every line.

Looking for help, i have input file like below and want to modify to expected output, if can without create additional file, hope can direct modify it. have 2 thing need do. 1st is adding a word (testplan generation off) after ! ! IPG: Tue Aug 07 14:31:17 2018 2nd is adding... (16 Replies)
Discussion started by: kttan
16 Replies

LEARN ABOUT ULTRIX

prev

prev(1mh)																 prev(1mh)

Name
       prev - show the previous message

Syntax
       prev [ +folder ] [ -[no]header ] [ -help ] [ -showproc program ] [ -noshowproc ] [ options to ]

Description
       The command displays the previous message in the current folder.  The previous message is the one before the current message in the folder.
       The message that is shown becomes the current message.

       You can specify a folder other than the current folder by using the +folder argument.  If you specify a folder, that  becomes  the  current
       folder.

Options
       -header
       -noheader Displays  a  one-line	header before the message.  The header consists of the name of the folder and the message number.  This is
		 the default behavior.	It can be suppressed with the -noheader option.

       -help	 Prints a list of the valid options to this command.

       -showproc program [ options ]
       -noshowproc
		 Specifies an alternative program to list messages.  The default is to use the program defined by the showproc: entry in the file.
		 As with you can give options to the program at the command line.  These are passed directly to by

       The defaults for this command are:

	      +folder defaults to the current folder
	      -header

Restrictions
       The  command  is  really  a  link  to  the program.  As a result, if you make a link to and that link is not called your link will act like
       instead.  To avoid this, add a profile-entry for the link to your MH profile and add the argument to the entry.

Examples
       The command in the following example displays the previous message in the folder
       $ prev +copylog

Profile Components
       Path:	   To determine your Mail directory
       showproc:   Program to show the message

Files
       The user profile.

See Also
       show(1mh), next(1mh)

																	 prev(1mh)
All times are GMT -4. The time now is 12:37 PM.
Unix & Linux Forums Content Copyright 1993-2022. All Rights Reserved.
Privacy Policy