Perl if condition parameters - linux

Question

I have a log file which looks like below:
4680 p4exp/v68 PJIANG-015394 25:34:19 IDLE none
8869 unnamed p4-python R integration semiconductor-project-trunktip-turbolinuxclient 01:33:52 IDLE none
8870 unnamed p4-python R integration remote-trunktip-osxclient 01:33:52
There are many such entries in the same log file such that some contains IDLE none at the end while some does not. I would like to retain the ones having "R integration" and "IDLE none" in a hash and ignore the rest. I have tried the following code but not getting the desired results.
#!/usr/bin/perl
open (FH,'/root/log.txt');
my %stat;
my ($killid, $killid_details);
while ($line = <FH>) {
if ($line =~ m/(\d+)/){
$killid = $1;
}
if ($line =~ /R integration/ and $line =~ /IDLE none/){
$killid_details = $line;
}
$stat{$killid} = {
killid => $killid_details
};
}
close (FH);
I am getting all the lines with R integration (for example I get 8869, 8870 lines) which should not be the case as 8870 should be ignored.
Please inform me if any mistake. I am still learning perl. Thank you.

Answer 1

I made a few changes in your program:
Always put in use strict; and use warnings;. These will catch 90% of your errors. (Although not this time).
When you open a file, you need to either use or die as in open my $fh, "<", $file or die qq(blah, blah, blah); or use use autodie; (which is now preferred). In your case, if the file didn't open, your program would have continued merrily along. You need to test whether or not the open statement worked.
Note my open statement. I use a variable for the file handle. This is preferred because it's not global, and it's easier to pass into subroutines. Also note I use the three parameter open. This way, you don't run into trouble if your file name begins with some strange character.
When you declare a variable, it's best to do it in scope. This way, variables go out of scope when you no longer need them. I moved where $killid and $killid_details to be declared inside the loop. That way, they no longer exist outside the loop.
You need to be more careful with your regular expressions. What if the phrase IDLE none appears elsewhere in your line? You only want it if its on the end of the line.
Now, for the issues you had:
You need to chomp lines when you read them. In Perl, the NL at the end of the line is read in. The chomp command removes it.
Your logic was a bit strange. You set $killid if your line had a digit in it (I modified it to look only for digits at the beginning of the line). However, you simply went on your merry way even if killid was not set. In your version, because you declared $killid outside of the loop, it had a value in each loop. Here I go to the next statement if $killid isn't defined.
You had a weird definition for your hash. You were defining a reference hash within a hash. No need for that. I made it a simple hash.
Here it is:
#! /usr/bin/env perl
use strict;
use warnings;
use feature qw(say);
use autodie;
use Data::Dumper;
open my $log_fh, '<', '/root/log.txt';
my %stat;
while (my $line = <$log_fh>) {
chomp $line;
next if not $line =~ /^(\d+)\s+/;
my $killid = $1;
if ($line =~ /R\s+integration/ and $line =~ /IDLE\s+none$/){
my $killid_details = $line;
$stat{$killid} = $killid_details;
}
}
close $log_fh;
say Dumper \%stat;

Answer 2

I think this is probably what you want:
while (<FH>) {
next unless /^(\d+).*R integration.*IDLE none/;
$stat{$1} = $_;
}
The regexp should be anchored to the beginning of the line, so you don't match a number anywhere on the line. There's no need to do multiple regexp matches, assuming the order of R integration and IDLE none are always as in the example. You need to use next when there's no match, so you don't process non-matching lines.
And I suspect that you just want to set the value of the hash entry to the string, not a reference to another hash.