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 



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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?



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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.



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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