You could replace the use of Win32::Process with a call to perl's built-in kill using a signal value of 2 (or 21 or -9 work, as do many others). 

use strict;
use Win32::Process::Info;

Win32::Process::Info->Set(variant=>'WMI');
my $pi = Win32::Process::Info->new();
for($pi->ListPids){
    my ($info) = $pi->GetProcInfo($_);
    if($info->{CommandLine} eq 'perl foo.pl a'){
         my $obj;
         my $pid = $info->{ProcessId};
         kill 2, $pid; 
         print "Killed $pid\n\n";
    }
}

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Lingua non convalesco, consenesco et abolesco. -- Rule 1 has a caveat! -- Who broke the cabal?
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In the absence of evidence, opinion is indistinguishable from prejudice.

In reply to Re^2: How to kill a windows process by command name? by BrowserUk
in thread How to kill a windows process by command name? by johnnywang

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