extract data from text file

Posted on 2011-02-17
Last Modified: 2012-06-21
I have a 30,000 file text file from which I need to extract data; I will start with example.

Let's say I have three network object-group in the file as A,B and C with different objects as below:

object-group network C
 network-object host
 network-object host
 network-object host
 network-object host
object-group network A
object-group network B
 network-object host
 network-object host

I need to extract group A and C from the file along with all other lines; i.e. line with object A and next 3 lines and then object C and next 4 lines.

Please help.
Question by:dpk_wal
  • 4
LVL 26

Accepted Solution

wilcoxon earned 300 total points
ID: 34923681
This should do it...

If you have any questions or it doesn't work as you'd like, let me know...

use strict;
use warnings;

# replace A and C with actual names
my %keeps = ('network A' => 1, 'network C' => 1);

# replace $file with actual filename
open IN, $file or die "could not open $file: $!";

my $keep;
while (<IN>) {
    if (m{^object-group\s+(.*?)\s*$}) {
        $keep = exists($keeps{$1}) ? 1 : 0;
    next unless $keep;
    # replace print with whatever you want to do with the lines
    # push them into an array if you want to keep them for later
    print $_, "\n";

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LVL 32

Author Comment

ID: 34923725
Thank you for quick post; in above can we also read A and B from a text file.
The file would have entries like:

LVL 32

Author Comment

ID: 34923745
Sorry for my limited knowledge with scripting, here is what I have done:
-rwxrwxrwx  1 root root 525 Feb 18 12:14 a
-rwxrwxrwx  1 root root 393 Feb 18 12:12 txtFile

Changed code above as:
open IN, $txtFile or die "could not open $txtFile: $!";

Getting error as below:
[root@myhost]# ./a
Global symbol "$txtFile" requires explicit package name at ./a line 10.
Global symbol "$txtFile" requires explicit package name at ./a line 10.
Execution of ./a aborted due to compilation errors.

Thank you for all your help.
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LVL 84

Assisted Solution

ozo earned 200 total points
ID: 34923853
open IN, "<txtFile" or die "could not open txtFile: $!";
LVL 32

Author Comment

ID: 34924039
Thank you for all the help.
LVL 32

Author Closing Comment

ID: 34924046
Thank you!

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