Hello Athanasius, Thanks for the suggestion, But im still getting the error :D I'm trying the code : 
#! perl
use strict;
use warnings;

$allmac = "~/temp/allmac.txt";
print $allmac;
while (my $line = $allmac)
{
    if ($line =~ /C4:46:19:75:C1:55/)
    {
        $id = (split /\s+/, $line)[0];
        print "ID = $id\n";
    }
}

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And getting error : 
Global symbol "$allmac" requires explicit package name at ./filtermac.
+pl line 5.
Global symbol "$allmac" requires explicit package name at ./filtermac.
+pl line 6.
Global symbol "$allmac" requires explicit package name at ./filtermac.
+pl line 7.
Global symbol "$id" requires explicit package name at ./filtermac.pl l
+ine 11.
Global symbol "$id" requires explicit package name at ./filtermac.pl l
+ine 12.
Execution of ./filtermac.pl aborted due to compilation errors.

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In reply to Re^2: grep in line and print by justbow
in thread grep in line and print by justbow

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