54 lines
1.3 KiB
Ruby
54 lines
1.3 KiB
Ruby
#
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# ping.rb -- check a host for upness
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#
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require 'timeout'
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require "socket"
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#= SYNOPSIS
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#
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# require 'ping'
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#
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# puts "'jimmy' is alive and kicking" if Ping.pingecho('jimmy', 10)
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#
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#= DESCRIPTION
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#
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# This module contains routines to test for the reachability of remote hosts.
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# Currently the only routine implemented is pingecho().
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#
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# pingecho() uses a TCP echo (_not_ an ICMP echo) to determine if the
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# remote host is reachable. This is usually adequate to tell that a remote
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# host is available to rsh(1), ftp(1), or telnet(1) to.
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#
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#= WARNING
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#
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# pingecho() may block for a long period if name resolution is slow. Require
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# 'resolv-replace' to use non-blocking name resolution.
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#
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module Ping
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# return true if we can open a connection to the hostname or IP address
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# +host+ on port +service+ (which defaults to the "echo" port) waiting up to
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# +timeout+ seconds.
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def pingecho(host, timeout=5, service="echo")
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begin
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timeout(timeout) do
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s = TCPSocket.new(host, service)
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s.close
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end
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rescue Errno::ECONNREFUSED
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return true
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rescue Timeout::Error, StandardError
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return false
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end
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return true
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end
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module_function :pingecho
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end
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if $0 == __FILE__
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host = ARGV[0]
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host ||= "localhost"
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printf("%s alive? - %s\n", host, Ping::pingecho(host, 5))
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end
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