Hi, I am seeking some Perl wisdom. I have wrote a small perl script to monitor a process and output to a file for X amount of time in a Linux/Unix env. 
use warnings;


# Some Variables

$pid = `pgrep -f '[a]bc'`;
$msg = "Alive";
$timestamp = localtime(time);

# Open file 

open $fh, '>>' , 'file.txt'  
    or die ( "Could not open file! $!\n" )
    ;

# Loop Condition

$i = 0;

until ($i > 60) {
    if ($pid) {
       $timestamp = localtime(time);
         print $fh ("$pid , $timestamp , $msg\n");
       $pid = `pgrep -f '[a]bc'`;
     }else{
       $timestamp = localtime(time);
        print $fh ("No pid , $timestamp\n"); 
       $pid = `pgrep -f '[a]bc'`;
     }
$i = $i +1;
sleep 10;
 }

print $fh ("Time over , $timestamp\n");

close $fh;

[download]
Now I face two problems that I would need your kind help if possible. First is that the print outcome in the file is using two line instead of one 
example:
9910 abc
 , Tue Sep 13 04:44:33 2016 , Alive

[download]
Second is that when the script is in "sleep 10" if I kill the PID the next print in the file will show that is still Alive. I have used IO::Handle and $|=1 to solve this but it didn't work. I don't use perl much possibly twice a year so apologies in advance if my questions are not appropriate. Any help will be much appreciate.

In reply to Help to monitor a PID by lsvolo

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