#!/usr/bin/perl -w
use strict;
use warnings;
use Getopt::Long;

#variable declaration
my $exec_mode;
my $param;
my $paramfile;
my $log_loc= "/logs/default_log.txt";
my $interv =2;

GetOptions( "e=s" => \$exec_mode, "p=s" => \$param, "pf=s" => \$paramfile, "l=s" => \log_loc, "i=i" => \$interv);

	if($exec_mode eq 'start')
	{
		if( $paramfile eq NULL)
		{
   			&startsar ($param, $interv);
		}
		else
		{
   			&startsar ($paramfile, $interv);
		}
	elsif($exec_mode eq 'stop')
                            {
			&stopsar ( $log_loc);
                            }
	else
              {
	print " usage sarexec -arguemrnts are-\n -e <start>/<stop>\n -p <params> \n -pf <param_file> \n -l <location> (by default location is '/logs/default_log.txt')\n -i <interval> ( by default interval is 2)\n "
              }

sub startsar 
{ 
              
              if (substr($_[0],0,1) eq "-")
                {
                    my $pid = fork();
                            if($pid>0)
                            {
                             #parent
                            }
                           else
                           {
                            system("sar  -o logfile $_[0]  $interval 0 > /dev/null&"); # this utility must run in background and able to close the script
		exit 0;
                           }   
                        
                }
                else 
                {
                  chomp $_[0];
                  my $param;
                            open FH,"< $_[0]" or die"cant open the file";
 		$param = <FH>;
 		close FH or die "cant close the file";
 		chomp($param);
                            my $pid = fork();
                            if($pid>0)
                            {
                             #parent
                            }
                           else
                           {
                            system("sar  -o logfile $param   $interval 0 > /dev/null&"); # this utility must run in background and able to close the script
		exit 0;
                           }
                  }
}

sub stopsar
{
	system("kill \$(pidof sadc)");
  	system("sar -f logfile>>$_[0]");
}