Class: Process::Daemon::Notification

Inherits:
Object
  • Object
show all
Defined in:
lib/process/daemon/notification.rb

Overview

This is a one shot cross-process notification mechanism using pipes. It can also be used in the same process if required, e.g. the self-pipe trick.

Instance Method Summary collapse

Constructor Details

#initialize ⇒ Notification

Returns a new instance of Notification.



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# File 'lib/process/daemon/notification.rb', line 25

def initialize
	@output, @input = IO.pipe
	
	@signalled = false
end

Instance Method Details

#signal ⇒ Object

Signal the notification.



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# File 'lib/process/daemon/notification.rb', line 32

def signal
	@signalled = true
	
	@input.puts
end

#signalled? ⇒ Boolean

Was this notification signalled?

Returns:

  • (Boolean) 


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# File 'lib/process/daemon/notification.rb', line 39

def signalled?
	@signalled
end

#wait(timeout: nil) ⇒ Object

Wait/block until a signal is received. Optional timeout.

Parameters:

  • timeout (Integer) (defaults to: nil) —

    the time to wait in seconds.



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# File 'lib/process/daemon/notification.rb', line 45

def wait(timeout: nil)
	if timeout
		read_ready, _, _ = IO.select([@output], [], [], timeout)
		
		return false unless read_ready and read_ready.any?
	end
	
	@signalled or @output.read(1)
	
	# Just in case that this was split across multiple processes.
	@signalled = true
end