Programming Perl

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7.2.46 Net::Ping - Check Whether a Host Is Online

use Net::Ping;
$hostname = 'elvis'; # host to check
$timeout = 10; # how long to wait for a response
print "elvis is alive\n" if pingecho($hostname, $timeout);

pingecho() uses a TCP echo (not an ICMP one) to determine whether a remote host is reachable. This is usually adequate to tell whether a remote host is available to rsh (1), ftp (1), or telnet (1).

The parameters for pingecho() are:

hostname: The remote host to check, specified either as a hostname or as an IP address.
timeout: The timeout in seconds. If not specified it will default to 5 seconds.

WARNING: pingecho() uses alarm to implement the timeout, so don't set another alarm while you are using it.

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