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Programming Perl

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The Standard Perl Library
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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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7.2.45 NDBM_File - Tied Access to NDBM FilesBook Index7.2.47 ODBM_File - Tied Access to ODBM Files