in reply to Re: Ping host
in thread Ping host

use warnings;

@hostnames = qw(goodhost badhost);

foreach (@hostnames){
    @a = `ping $_`;
    print "for $_ checking.....";
    if ("@a" =~ /please check/){
        print " For $_ : host not available.";
    }
check/;
}

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All I wanted to say: badhost : host not available But doesnt work

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Re^3: Ping host
by almut (Canon) on Oct 28, 2009 at 16:03 UTC

    Maybe you want to check case-insensitively, i.e. /please check/i

    The ping on my Windows box outputs for example: 

    Ping request could not find host badhost. Please check the name and tr
+y again.

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Re^3: Ping host
by jakobi (Pilgrim) on Oct 28, 2009 at 16:12 UTC

    Some notes:

    • also add use strict, please
    • line 11: check/ certainly fails to parse
    • check your OS documentation on you flavour of ping: you may be able to use the return code on e.g. Unix or Cygwin: system("ping -c3 $host"); warn if $?;
    • why @a=`` and "@a"=~ // instead of the simpler $a=`ping -c3 host 2>&1` or similar?
      I use 2?&1 to include output on stderr instead of just stdout; this might be part of your problem or just me subscribing to an overly cautious cargo-cult :).
    • finally there's also Net::Ping

    Resulting in e.g. this example, which should also run on e.g. cygwin:

    use strict;
use warnings;
my @hostnames = qw(www.leo.org dhbvg.xxx);
foreach (@hostnames){
   # my $a = `echo pinging $_ 1>&2 ; ping -c3 $_ 2>&1 | tee -a /dev/tt
+y`;
   my $a = `ping -c3 $_ 2>&1`;
   if ($a =~ /unreach|unknown host/i){
      print " For $_ : problems: $a.";
   }
}

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    cu & HTH, Peter -- hints may be untested unless stated otherwise; use with caution & understanding.
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      I use 2>&1 to include output on stderr instead of just stdout

      Though this is generally a good idea, the native Windows ping (which is the only one known to me to ever output "Please check...") appears to write to stdout. I.e., this works fine for me: 

      perl -le "print `ping badhost` =~ /please check/i ? 'bad':'good'"

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