"... atleast that is what I want..!"

and I want a pony... but I've never found a hayburner in my Christmas stocking.

Others monks have explained the shortcomings of your eval print $param; but, for emphasis:

>perl 848064_xyz.pl 'egal("20090316","7006")'


         'egal(20090316,7006)' is $param at line 10

'egal(20090316,7006)'
        Line 11 $param: |'egal(20090316,7006)'|

 At 13, $test: 'egal(20090316,7006)'

Use of uninitialized value in concatenation (.) or string at 848064_xy
+z.pl line 22.

++++
>
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And, just BTW, note that your double_quotes -- the "s -- don't pass through the windows shell (my Linux box is down, but IIRC, you'll have a mirror-image issue there).

Here's your code, slightly modified at 5, 6, 9, 10, 12, 19 and 34 for illustration (thus, "line 26" in my previous reply is now line 38).

#!/usr/bin/perl
use strict;
use warnings;

# OP says: Now I am calling the script :
# 001: perl xyz.pl 'egal("20090316","7006")'

my $param = shift;
chomp $param;
print "\n\n\t $param is \$param at line 10\n\n";
eval print $param;
print "\n\tLine 11 \$param: |$param| \n";

sub egal {
        my $result;
        my @arg = @_;

        my $test = $arg[0];
        print "\n At 13, \$test: $test\n\n";

        my @test = grep (/$test/i, @arg);
        print "\t $test[0] \n";
        print "++++";

        if ($#test == $#arg)
        {
                $result = 'true';
        }
        else
        {
                $result = 'false';
        }
        return $result;
        print " $result\n";
}


egal($param);         # call the sub!
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