Many Thanks for immediate replies. Sorry I forgot to mention that there are lines in the log file beginning with Starting which need to considered but there are also lines beginning with Starting stop module name - which are not to be considered, Please suggest how to get rid of these lines in the array @linetypes mentioned in the solution provided? I am trying like this, Kindly suggest:

use strict;
use warnings;

my @starting=();
my @success=();
my @linetypes = ("Starting", "SUCCESS: Completed");
my $linetypes_re = join("|", @linetypes);

open (LG, "path of the os.log");

@log=<LG>;

for my $line (@log)
{
    chomp $line;
    next unless $line;
    my ($linetype, $moudle, $year, $month, $day, $hh, $mm) = $line =~ 
+m/^($linetypes_re) (.+$) at (\d{4})-(\d{2})-(\d{2})-(\d{2})(\d{2})\.$
+/
    my $info = [$module, $year, $month, $day, $hh, $mm];
    if ($linetype eq $linetypes[0]) {
        push @starting, $info;
    } elsif ($linetype eq $linetypes[1]) {
        push @succes, $info;
        }
}
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