I have a file containing the output after pinging several IP addresses. For example, the first line is "12.34.56.78 is alive" and line 2 is "no answer from 12.34.56.79" and so on. I am trying to print only those lines that contain the words "is alive." I tried several things including grep and if-else statements but only want those lines containing "is alive" to print to a separate file & am having no luck. Heres what I have so far: 
# Create a list of all possible IP addresses within subnet
open(ALLIP, ">allip.list") || die "Unable to create file: allip.list\n
+";
for ($i=0; $i<=20; $i++) {
        print ALLIP "$ip_subnet.$i\n";
        }
close(ALLIP);

open(ALLIP, "allip.list") || die "Unable to open file: allip.list\n";
open(PINGALLIP, ">pingallip.list") || die "Unable to open file: pingal
+lip.list";
while (<ALLIP>) {
        chomp;
        system("ping $_ >>pingallip.list") && "Unable to create file: 
+pingallip.
list";
        }
close(ALLIP);
close(PINGALLIP);

open(ALIVEIP, ">aliveip.list");
close(ALIVEIP);
open(ALIVEIP, "aliveip.list");
open(PINGALLIP, "pingallip.list") || die "Unable to open file: pingall
+ip.list";
while (<PINGALLIP>) {
   if (/is alive/) {
                chomp;
                print ALIVEIP $_;
        }
}
close(PINGALLIP);

[download]
Any help would be greatly appreciated. The idea of using the IP module has already been mentioned to me but I am also using this as an excuse to improve my perl skills. =) Thanks.

Zuinc

In reply to Printing matched lines by zuinc

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