how do I test against each element in an array

dallok has asked for the wisdom of the Perl Monks concerning the following question:

have alist of machines I need to ping these machine names are in a file I turned into an Array. How do I test each element of the array and return the result of the ping (specifically the IP address to another file.) this is what I have so far.

#! c:\perl\bin -w

 my $NAMES = "c:/names.txt";
 open NAMES, $NAMES or die "DOH cannot open $NAMES";
  @NAMELIST=<NAMES>;
  chomp(@NAMELIST);
    foreach $NAME (@NAMELIST) {
      open TESTED, '>>C:\tested.txt';
       system('c:\winnt\system32\ping.exe -n 1 -w 75 "$NAME"');
      print TESTED "$NAME\n";
      close TESTED;
    }
 close NAMES;
exit 0;
[download]

Any thoughts. I know that the print TESTED "$NAME\n" is incorrect but not sure how to get the return from the ping request?

Originally posted as a Categorized Question.

Comment on how do I test against each element in an array Download Code

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Re: how do I test against each element in an array by chromatic (Archbishop) on Nov 07, 2000 at 22:44 UTC
This is a perlfaq, specifically in perlfaq8 under Why can't I get the output of a command with system()?. Originally posted as a Categorized Answer.	[reply]
Re: how do I test against each element in an array by little (Curate) on Nov 07, 2000 at 22:46 UTC
And all the answers to your problem you can find in the examples to the module: Net::Ping see, perls makes it easy :-) Originally posted as a Categorized Answer.	[reply]
Re: how do I test against each element in an array by kilinrax (Deacon) on Nov 07, 2000 at 22:45 UTC
This works on my system, (linux, so you'll need to tweak the locations of things), though it's a bit of a kludge. #!/usr/bin/perl -w open NAMES, "names.txt" or die "Cannot open names file"; while (<NAMES>) { chomp; my $ping = `ping -c 1 $_`; if ($ping =~ /$(\d+\.\d+\.\d+\.\d+)$/) { my $ip = $1; open TESTED, '>>tested.txt'; print TESTED "$ip\n"; close TESTED; } else { warn "Cannot deciper result of \"ping $_\""; } } close NAMES; exit 0; [download] Originally posted as a Categorized Answer.	[reply] [d/l]
Re: how do I test against each element in an array by davorg (Chancellor) on Nov 07, 2000 at 22:45 UTC
To get the results from a command, you should look at the back-quotes (`cmd`) or qx() operators. Both are documented in perlop. Originally posted as a Categorized Answer.	[reply]
Re: how do I test against each element in an array by the_slycer (Chaplain) on Nov 07, 2000 at 22:51 UTC
If you are trying to get the IP vs hostname, I would suggest using Socket and inet_ntoa(scalar(gethostbyname($host))); So, something like this (untested): `use strict; use Socket; my $ip; open (NAMES, "<c:/names.txt") \|\| die "Could not open c:/names.txt: $!" +; my @hosts=<NAMES>; close NAMES; chomp (@hosts); open (IPS, ">someoutputfile.txt") \|\| die "Could not create file: $!"; foreach (@hosts){ $ip = inet_ntoa(scalar(gethostbyname($_))); print IPS "$_\n"; } close IPS;` [download] Originally posted as a Categorized Answer.	[reply] [d/l]