class ThreadsWait

This class watches for termination of multiple threads. Basic functionality (wait until specified threads have terminated) can be accessed through the class method ::all_waits. Finer control can be gained using instance methods.

Example:

ThreadsWait.all_waits(thr1, thr2, ...) do |t|
 STDERR.puts "Thread #{t} has terminated."
end
th = ThreadsWait.new(thread1,...)
th.next_wait # next one to be done

Constants

RCS_ID

Attributes

threads[R]

Returns the array of threads that have not terminated yet.

Public Class Methods

all_waits(*threads) { |thread| ... } click to toggle source

Waits until all specified threads have terminated. If a block is provided, it is executed for each thread as they terminate.

# File lib/thwait.rb, line 38
def ThreadsWait.all_waits(*threads) # :yield: thread
 tw = ThreadsWait.new(*threads)
 if block_given?
 tw.all_waits do |th|
 yield th
 end
 else
 tw.all_waits
 end
end

new(*threads) click to toggle source

Creates a ThreadsWait object, specifying the threads to wait on. Non-blocking.

# File lib/thwait.rb, line 53
def initialize(*threads)
 @threads = []
 @wait_queue = Queue.new
 join_nowait(*threads) unless threads.empty?
end

Public Instance Methods

all_waits() { |th| ... } click to toggle source

Waits until all of the specified threads are terminated. If a block is supplied for the method, it is executed for each thread termination.

Raises exceptions in the same manner as next_wait.

# File lib/thwait.rb, line 126
def all_waits
 until @threads.empty?
 th = next_wait
 yield th if block_given?
 end
end

empty?() click to toggle source

Returns true if there are no threads in the pool still running.

# File lib/thwait.rb, line 65
def empty?
 @threads.empty?
end

finished?() click to toggle source

Returns true if any thread has terminated and is ready to be collected.

# File lib/thwait.rb, line 72
def finished?
 !@wait_queue.empty?
end

join(*threads) click to toggle source

Waits for specified threads to terminate, and returns when one of the threads terminated.

# File lib/thwait.rb, line 80
def join(*threads)
 join_nowait(*threads)
 next_wait
end

join_nowait(*threads) click to toggle source

Specifies the threads that this object will wait for, but does not actually wait.

# File lib/thwait.rb, line 89
def join_nowait(*threads)
 threads.flatten!
 @threads.concat threads
 for th in threads
 Thread.start(th) do |t|
 begin
 t.join
 ensure
 @wait_queue.push t
 end
 end
 end
end

next_wait(nonblock = nil) click to toggle source

Waits until any of the specified threads has terminated, and returns the one that does.

If there is no thread to wait, raises ErrNoWaitingThread. If nonblock is true, and there is no terminated thread, raises ErrNoFinishedThread.

# File lib/thwait.rb, line 110
def next_wait(nonblock = nil)
 ThreadsWait.fail ErrNoWaitingThread if @threads.empty?
 begin
 @threads.delete(th = @wait_queue.pop(nonblock))
 th
 rescue ThreadError
 ThreadsWait.fail ErrNoFinishedThread
 end
end