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Old 10-29-2012, 02:21 PM   #1
Ziddy
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Question [Perl] Reading multiple lines from a file


Hey there.
I'm not too sure how to phrase this, which seems to be why I'm having such a hard time finding an answer.
What I'm trying to do is...
Open a file and read the line. Say the line looks like this. "IP_Address username password". I want the IP in one variable, the UN in another and the PW in another. Then I do what I wish with them through other code, once finished, it moves on to the next line, formatted the same way. (IP UN PW).

Sorry that sounds so confusing. I know how read the entire line, then execute code and continue to the next, just not with arguments AFTER, on the same line.

Thanks for your time.

Last edited by Ziddy; 10-29-2012 at 05:30 PM.
 
Old 10-29-2012, 02:48 PM   #2
Habitual
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Without knowing how much perl skill you have, here's a basic workup on opening a file and reading line-by-line while looking for text.

This code probably does NOT work OOTB. so some Perl kung-fu will be necessary.

Code:
my $dataFile = "/path/to/my/file";
open LOG, "<$dataFile";
while (<LOG>) {
$line = $_;
next if ($line=~ /^\s*#/); # ignore comment lines
 if($line =~ /(\d+\.\d+\.\d+\.\d+)(\w+)(\w+)/)
 print "$1 $2 $3\n";
I wrote a similar functioning script here... that probably can be modified to suit your purpose.
Without some sample data it would be a guessing game at best.
 
Old 10-29-2012, 03:11 PM   #3
Ziddy
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I evidently need to learn more about built in commands.
it spits out the ip for $1, but a number for $2/$3. Single digit.

Let's say in the file we have
11.22.33.44 hello world
22.33.44.55 world hello

$1 = 11.22.33.44
$2 = hello
$3 = world
is what I'm after. Then it executes code after assigning variables, moves on to the next line in the file, overwriting the variables, repeats until end of file. $1 becomes 22.33.44.55 after it's done with the 11.22.33.44 line. I know I'm making this more complicated than it has to be, as I usually do. Thanks fr your reply, I'm still messing with it.


Edit: I believe I'm on to something here. The only problem is not all lines have 3 arguments which seems to mess with it.

Edit2: Figured it out. Works quite well. Thanks for all the help. For those wondering:

open(INPUT_FILE, "check.txt") or die "check.txt NOT FOUND!\n";
my @list = <INPUT_FILE>;
close(INPUT_FILE);
for my $line (@list) {
if($line =~ /(\d+\.\d+\.\d+\.\d+) (\w+) (\w+)/) {
print "Checking $1 - $2 - $3:\t ";
}
etc etc.

Last edited by Ziddy; 10-29-2012 at 05:29 PM.
 
Old 10-30-2012, 08:27 AM   #4
Habitual
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Your Perl.fu is better than mine.
 
  


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