Welcome to the monastry, you need to chomp $url to remove the newline from the end of the url.

It is also highly recommended that you use strict and warnings, believe me it is well worth it.

Here is a modified version of your script which includes a print before and after a chomp to highlight the difference.

use strict;
use warnings;

use Net::Ping;

my $url = <>;

print ":$url:\n";
chomp($url);
print ":$url:\n";

my $p = Net::Ping->new();

if ( $p->ping($url) ) {
    print "working\n";
}
else {
    print "not working\n"; 
}
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Output:

:www.bbc.co.uk
:
:www.bbc.co.uk:
working
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Thank you so much it worked, I will try to ask harder next time, I am learning java in the school and Perl has some unusual codes for me:)

You did not chomp your input, so $url contains a new line if you don't run the script with the url on the command line. If you do run it on the command line, the diamond operator actually is looking for file names. By default Net::Ping attempts to establish a connection to the remote host's echo port via TCP, which may not be what you expect, since normal OS ping is an ICMP ping. If you want this behavior, 'icmp' has to be passed to the Net::Ping constructor.

#!/usr/bin/env perl

use Net::Ping;

$url = <>;
chomp $url;
$p = Net::Ping->new('icmp');
if ($p->ping($url)) {
    print "working";
}
else {print "not working"; }
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~$ cat text
yahoo.com
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