[SOLVED] Changing pattern from string in Perl

rahul_dubeyin · 06-03-2011, 06:29 AM

Hi All,

I am new to perl and not able to understand all the pattern matching.

I using this script to send the status to another Nagios server using ncsa. Nsca don't transmit "()" So I need to remove them before sending.

Currently I am using

Code:

$opt_a =~ s/\(/"\(/;
$opt_a =~ s/\)/"\)"/;

for the string

Quote:

ARCServe Minor Trap. BK-LO-BAK01 BK-LO-BAK01: [JobID:1931 NEW JOB - London Servers Backup] Backup Operation Incomplete.Number of Error(s)/Warning(s): 9/5

This is working fine but its is not working when there is change inside the bracket for e.g
(6290)

I want help to change this code to work for any change with in the brackets.
Ask me if I am not clear.

grail · 06-03-2011, 06:41 AM

Would you mind providing a second example of what does not work?
It is not clear how adding a different string between () affects your process?

rahul_dubeyin · 06-03-2011, 07:58 AM

Here is the second example.

Quote:

Power Redundancy Lost (6032): The Power Supplies are no longer redundant on Chassis 0.

The above mentioned code is not working for this scenario. The number between the () is keep on changing in every string.

grail · 06-03-2011, 08:42 AM

hmmmm ... I might be missing something, but it appears to me that the result for both strings is the same, although personally I am not sure I would desire either outcome.

Here is what I tested:

Code:

#!/usr/bin/perl
use warnings;
use strict;

my $opt_a = "ARCServe Minor Trap. BK-LO-BAK01 BK-LO-BAK01: [JobID:1931 NEW JOB - London Servers Backup] Backup Operation Incomplete.Number of Error(s)/Warning(s): 9/5";

$opt_a =~ s/\(/"\(/;
$opt_a =~ s/\)/"\)"/;

print $opt_a . "\n";

$opt_a = "Power Redundancy Lost (6032): The Power Supplies are no longer redundant on Chassis 0.";

$opt_a =~ s/\(/"\(/;
$opt_a =~ s/\)/"\)"/;

print $opt_a . "\n";

When run I get the following output:

Code:

ARCServe Minor Trap. BK-LO-BAK01 BK-LO-BAK01: [JobID:1931 NEW JOB - London Servers Backup] Backup Operation Incomplete.Number of Error"(s")"/Warning(s): 9/5
Power Redundancy Lost "(6032")": The Power Supplies are no longer redundant on Chassis 0.

I have highlighted the changes made to the strings in red.

The affect appears to be the same for both strings ... that I can see. Or am I missing something?

rahul_dubeyin · 06-03-2011, 11:54 AM

Quote:

Originally Posted by grail

hmmmm ... I might be missing something, but it appears to me that the result for both strings is the same, although personally I am not sure I would desire either outcome.

The affect appears to be the same for both strings ... that I can see. Or am I missing something?

My apologies here I pasted code from the testing script.

here is the correct code.

Code:

$opt_a =~ s/\(s\)//;

I am using it twice because first string have two occurrence of (s)

Sergei Steshenko · 06-03-2011, 11:58 AM

Quote:

Originally Posted by rahul_dubeyin

My apologies here I pasted code from the testing script.

here is the correct code.

Code:

$opt_a =~ s/\(s\)//;

Why do you have the item in red ?

rahul_dubeyin · 06-03-2011, 12:00 PM

Quote:

Originally Posted by Sergei Steshenko

Why do you have the item in red ?

The code will replace (s) to null(nothing).

grail · 06-03-2011, 12:03 PM

So of course this will not work if the brackets do not contain a space. Although copying what you have there does not appear to be a space between the second set
of brackets. What is it you would like to happen?

rahul_dubeyin · 06-03-2011, 12:11 PM

Quote:

Originally Posted by grail

So of course this will not work if the brackets do not contain a space. Although copying what you have there does not appear to be a space between the second set
of brackets. What is it you would like to happen?

Grail, thanks for taking interest.

The code

Code:

$opt_a =~ s/\(s\)//;

will work for (s) but not for (6299). SO I need help to change it to work. Remember please, the number between the bracket will keep on changing.

Sergei Steshenko · 06-03-2011, 12:16 PM

Quote:

Originally Posted by rahul_dubeyin

G
...
will work for (s) but not for (6299). SO I need help to change it to work. Remember please, the number between the bracket will keep on changing.

See http://perldoc.perl.org/perlrequick.html -> http://perldoc.perl.org/perlrequick....racter-classes ; look for the 'digit' word, then read http://perldoc.perl.org/perlrequick....ng-repetitions .

grail · 06-04-2011, 04:54 AM

As an addition to Sergei's helpful links, you may want to look up how to find everything except the last thing you wish to find. I am being a little cryptic so you have
a chance to work it out, but I believe, if I understand correctly, that the scenario you have is that you wish to replace any and all occurrences of (anything here) ... is this correct?

If so I believe my previous tip will help

If not and you are only interested in replacing brackets with numbers inside, then Sergei's advice is the way to go (his links are still
great advice either way

)

theNbomr · 06-05-2011, 10:21 AM

To aid in solving these kinds of problems, I find it almost always easier to describe in words, what operation you are trying to accomplish. Almost always, the phrases that describe your operation map directly to regex elements. Your case seem to be: 'replace strings of digits between closed parentheses with the same inside double quotes'. Here, the phrases 'replace', 'string of digits' & 'the same', map directly to regex notation. The rest is just matching single characters, or adding single characters. Your job is just to identify what the regex elements are, and put them together to make a regex that operates according to your spec.
--- rod.

rahul_dubeyin · 06-06-2011, 04:41 AM

Hmm Thanks all of you.

grail · 06-06-2011, 05:05 AM

Don't forget to show your solution to help others

and then mark thread as SOLVED

rahul_dubeyin · 06-06-2011, 08:08 AM

Yes grail. Here I am.

You were correct about it, has to be the same way. The only difference is that I have to do it twice.

Code:

$opt_a =~ s/\(//;
$opt_a =~ s/\)//;

In first it will replace the "(" by null and in second command it will replace the ")" by null.