FM / ruby-2.7.8

/opt/cpanel/ea-ruby27/root/usr/share/ruby/ruby-2.7.8/

/opt/cpanel/ea-ruby27/root/usr/share/ruby/ruby-2.7.8

Name	Size	Mode	Actions
benchmark/	-	0755	rm
bigdecimal/	-	0755	rm
bundler/	-	0755	rm
cgi/	-	0755	rm
csv/	-	0755	rm
delegate/	-	0755	rm
did_you_mean/	-	0755	rm
digest/	-	0755	rm
drb/	-	0755	rm
fiddle/	-	0755	rm
forwardable/	-	0755	rm
getoptlong/	-	0755	rm
io/	-	0755	rm
irb/	-	0755	rm
json/	-	0755	rm
logger/	-	0755	rm
matrix/	-	0755	rm
net/	-	0755	rm
observer/	-	0755	rm
open3/	-	0755	rm
openssl/	-	0755	rm
optparse/	-	0755	rm
ostruct/	-	0755	rm
pstore/	-	0755	rm
psych/	-	0755	rm
racc/	-	0755	rm
rdoc/	-	0755	rm
reline/	-	0755	rm
rexml/	-	0755	rm
rinda/	-	0755	rm
ripper/	-	0755	rm
rss/	-	0755	rm
rubygems/	-	0755	rm
singleton/	-	0755	rm
syslog/	-	0755	rm
timeout/	-	0755	rm
tracer/	-	0755	rm
unicode_normalize/	-	0755	rm
uri/	-	0755	rm
webrick/	-	0755	rm
yaml/	-	0755	rm
abbrev.rb	3529	0644	edit dl rm
base64.rb	3379	0644	edit dl rm
benchmark.rb	18453	0644	edit dl rm
bigdecimal.rb	24	0644	edit dl rm
bundler.rb	23718	0644	edit dl rm
cgi.rb	10037	0644	edit dl rm
coverage.rb	368	0644	edit dl rm
csv.rb	55643	0644	edit dl rm
date.rb	1066	0644	edit dl rm
debug.rb	30624	0644	edit dl rm
delegate.rb	11343	0644	edit dl rm
did_you_mean.rb	3806	0644	edit dl rm
digest.rb	2894	0644	edit dl rm
drb.rb	50	0644	edit dl rm
English.rb	6258	0644	edit dl rm
erb.rb	29504	0644	edit dl rm
expect.rb	2217	0644	edit dl rm
fiddle.rb	1722	0644	edit dl rm
fileutils.rb	49271	0644	edit dl rm
find.rb	2526	0644	edit dl rm
forwardable.rb	9130	0644	edit dl rm
getoptlong.rb	15787	0644	edit dl rm
ipaddr.rb	19989	0644	edit dl rm
irb.rb	27603	0644	edit dl rm
json.rb	1809	0644	edit dl rm
kconv.rb	5861	0644	edit dl rm
logger.rb	16792	0644	edit dl rm
matrix.rb	61703	0644	edit dl rm
mkmf.rb	88539	0644	edit dl rm
monitor.rb	6920	0644	edit dl rm
mutex_m.rb	2214	0644	edit dl rm
observer.rb	5971	0644	edit dl rm
open-uri.rb	26088	0644	edit dl rm
open3.rb	22336	0644	edit dl rm
openssl.rb	469	0644	edit dl rm
optionparser.rb	59	0644	edit dl rm
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pathname.rb	16558	0644	edit dl rm
pp.rb	15978	0644	edit dl rm
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prime.rb	12670	0644	edit dl rm
pstore.rb	15063	0644	edit dl rm
psych.rb	21718	0644	edit dl rm
racc.rb	137	0644	edit dl rm
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resolv-replace.rb	1805	0644	edit dl rm
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ripper.rb	2494	0644	edit dl rm
rss.rb	2963	0644	edit dl rm
rubygems.rb	39108	0644	edit dl rm
securerandom.rb	9528	0644	edit dl rm
set.rb	24622	0644	edit dl rm
shellwords.rb	6816	0644	edit dl rm
singleton.rb	4158	0644	edit dl rm
socket.rb	44702	0644	edit dl rm
tempfile.rb	11213	0644	edit dl rm
time.rb	24590	0644	edit dl rm
timeout.rb	4075	0644	edit dl rm
tmpdir.rb	4142	0644	edit dl rm
tracer.rb	6640	0644	edit dl rm
tsort.rb	14642	0644	edit dl rm
un.rb	10202	0644	edit dl rm
uri.rb	3039	0644	edit dl rm
weakref.rb	1473	0644	edit dl rm
webrick.rb	6890	0644	edit dl rm
yaml.rb	1845	0644	edit dl rm

Edit: /opt/cpanel/ea-ruby27/root/usr/share/ruby/ruby-2.7.8/open3.rb (22336B)

# frozen_string_literal: true

#
# = open3.rb: Popen, but with stderr, too
#
# Author:: Yukihiro Matsumoto
# Documentation:: Konrad Meyer
#
# Open3 gives you access to stdin, stdout, and stderr when running other
# programs.
#

#
# Open3 grants you access to stdin, stdout, stderr and a thread to wait for the
# child process when running another program.
# You can specify various attributes, redirections, current directory, etc., of
# the program in the same way as for Process.spawn.
#
# - Open3.popen3 : pipes for stdin, stdout, stderr
# - Open3.popen2 : pipes for stdin, stdout
# - Open3.popen2e : pipes for stdin, merged stdout and stderr
# - Open3.capture3 : give a string for stdin; get strings for stdout, stderr
# - Open3.capture2 : give a string for stdin; get a string for stdout
# - Open3.capture2e : give a string for stdin; get a string for merged stdout and stderr
# - Open3.pipeline_rw : pipes for first stdin and last stdout of a pipeline
# - Open3.pipeline_r : pipe for last stdout of a pipeline
# - Open3.pipeline_w : pipe for first stdin of a pipeline
# - Open3.pipeline_start : run a pipeline without waiting
# - Open3.pipeline : run a pipeline and wait for its completion
#

module Open3

# Open stdin, stdout, and stderr streams and start external executable.
  # In addition, a thread to wait for the started process is created.
  # The thread has a pid method and a thread variable :pid which is the pid of
  # the started process.
  #
  # Block form:
  #
  #   Open3.popen3([env,] cmd... [, opts]) {|stdin, stdout, stderr, wait_thr|
  #     pid = wait_thr.pid # pid of the started process.
  #     ...
  #     exit_status = wait_thr.value # Process::Status object returned.
  #   }
  #
  # Non-block form:
  #
  #   stdin, stdout, stderr, wait_thr = Open3.popen3([env,] cmd... [, opts])
  #   pid = wait_thr[:pid]  # pid of the started process
  #   ...
  #   stdin.close  # stdin, stdout and stderr should be closed explicitly in this form.
  #   stdout.close
  #   stderr.close
  #   exit_status = wait_thr.value  # Process::Status object returned.
  #
  # The parameters env, cmd, and opts are passed to Process.spawn.
  # A commandline string and a list of argument strings can be accepted as follows:
  #
  #   Open3.popen3("echo abc") {|i, o, e, t| ... }
  #   Open3.popen3("echo", "abc") {|i, o, e, t| ... }
  #   Open3.popen3(["echo", "argv0"], "abc") {|i, o, e, t| ... }
  #
  # If the last parameter, opts, is a Hash, it is recognized as an option for Process.spawn.
  #
  #   Open3.popen3("pwd", :chdir=>"/") {|i,o,e,t|
  #     p o.read.chomp #=> "/"
  #   }
  #
  # wait_thr.value waits for the termination of the process.
  # The block form also waits for the process when it returns.
  #
  # Closing stdin, stdout and stderr does not wait for the process to complete.
  #
  # You should be careful to avoid deadlocks.
  # Since pipes are fixed length buffers,
  # Open3.popen3("prog") {|i, o, e, t| o.read } deadlocks if
  # the program generates too much output on stderr.
  # You should read stdout and stderr simultaneously (using threads or IO.select).
  # However, if you don't need stderr output, you can use Open3.popen2.
  # If merged stdout and stderr output is not a problem, you can use Open3.popen2e.
  # If you really need stdout and stderr output as separate strings, you can consider Open3.capture3.
  #
  def popen3(*cmd, &block)
    if Hash === cmd.last
      opts = cmd.pop.dup
    else
      opts = {}
    end

in_r, in_w = IO.pipe
    opts[:in] = in_r
    in_w.sync = true

out_r, out_w = IO.pipe
    opts[:out] = out_w

err_r, err_w = IO.pipe
    opts[:err] = err_w

popen_run(cmd, opts, [in_r, out_w, err_w], [in_w, out_r, err_r], &block)
  end
  module_function :popen3

# Open3.popen2 is similar to Open3.popen3 except that it doesn't create a pipe for
  # the standard error stream.
  #
  # Block form:
  #
  #   Open3.popen2([env,] cmd... [, opts]) {|stdin, stdout, wait_thr|
  #     pid = wait_thr.pid # pid of the started process.
  #     ...
  #     exit_status = wait_thr.value # Process::Status object returned.
  #   }
  #
  # Non-block form:
  #
  #   stdin, stdout, wait_thr = Open3.popen2([env,] cmd... [, opts])
  #   ...
  #   stdin.close  # stdin and stdout should be closed explicitly in this form.
  #   stdout.close
  #
  # See Process.spawn for the optional hash arguments _env_ and _opts_.
  #
  # Example:
  #
  #   Open3.popen2("wc -c") {|i,o,t|
  #     i.print "answer to life the universe and everything"
  #     i.close
  #     p o.gets #=> "42\n"
  #   }
  #
  #   Open3.popen2("bc -q") {|i,o,t|
  #     i.puts "obase=13"
  #     i.puts "6 * 9"
  #     p o.gets #=> "42\n"
  #   }
  #
  #   Open3.popen2("dc") {|i,o,t|
  #     i.print "42P"
  #     i.close
  #     p o.read #=> "*"
  #   }
  #
  def popen2(*cmd, &block)
    if Hash === cmd.last
      opts = cmd.pop.dup
    else
      opts = {}
    end

in_r, in_w = IO.pipe
    opts[:in] = in_r
    in_w.sync = true

out_r, out_w = IO.pipe
    opts[:out] = out_w

popen_run(cmd, opts, [in_r, out_w], [in_w, out_r], &block)
  end
  module_function :popen2

# Open3.popen2e is similar to Open3.popen3 except that it merges
  # the standard output stream and the standard error stream.
  #
  # Block form:
  #
  #   Open3.popen2e([env,] cmd... [, opts]) {|stdin, stdout_and_stderr, wait_thr|
  #     pid = wait_thr.pid # pid of the started process.
  #     ...
  #     exit_status = wait_thr.value # Process::Status object returned.
  #   }
  #
  # Non-block form:
  #
  #   stdin, stdout_and_stderr, wait_thr = Open3.popen2e([env,] cmd... [, opts])
  #   ...
  #   stdin.close  # stdin and stdout_and_stderr should be closed explicitly in this form.
  #   stdout_and_stderr.close
  #
  # See Process.spawn for the optional hash arguments _env_ and _opts_.
  #
  # Example:
  #   # check gcc warnings
  #   source = "foo.c"
  #   Open3.popen2e("gcc", "-Wall", source) {|i,oe,t|
  #     oe.each {|line|
  #       if /warning/ =~ line
  #         ...
  #       end
  #     }
  #   }
  #
  def popen2e(*cmd, &block)
    if Hash === cmd.last
      opts = cmd.pop.dup
    else
      opts = {}
    end

in_r, in_w = IO.pipe
    opts[:in] = in_r
    in_w.sync = true

out_r, out_w = IO.pipe
    opts[[:out, :err]] = out_w

popen_run(cmd, opts, [in_r, out_w], [in_w, out_r], &block)
  end
  module_function :popen2e

def popen_run(cmd, opts, child_io, parent_io) # :nodoc:
    pid = spawn(*cmd, opts)
    wait_thr = Process.detach(pid)
    child_io.each(&:close)
    result = [*parent_io, wait_thr]
    if defined? yield
      begin
        return yield(*result)
      ensure
        parent_io.each(&:close)
        wait_thr.join
      end
    end
    result
  end
  module_function :popen_run
  class << self
    private :popen_run
  end

# Open3.capture3 captures the standard output and the standard error of a command.
  #
  #   stdout_str, stderr_str, status = Open3.capture3([env,] cmd... [, opts])
  #
  # The arguments env, cmd and opts are passed to Open3.popen3 except
  # <code>opts[:stdin_data]</code> and <code>opts[:binmode]</code>.  See Process.spawn.
  #
  # If <code>opts[:stdin_data]</code> is specified, it is sent to the command's standard input.
  #
  # If <code>opts[:binmode]</code> is true, internal pipes are set to binary mode.
  #
  # Examples:
  #
  #   # dot is a command of graphviz.
  #   graph = <<'End'
  #     digraph g {
  #       a -> b
  #     }
  #   End
  #   drawn_graph, dot_log = Open3.capture3("dot -v", :stdin_data=>graph)
  #
  #   o, e, s = Open3.capture3("echo abc; sort >&2", :stdin_data=>"foo\nbar\nbaz\n")
  #   p o #=> "abc\n"
  #   p e #=> "bar\nbaz\nfoo\n"
  #   p s #=> #<Process::Status: pid 32682 exit 0>
  #
  #   # generate a thumbnail image using the convert command of ImageMagick.
  #   # However, if the image is really stored in a file,
  #   # system("convert", "-thumbnail", "80", "png:#{filename}", "png:-") is better
  #   # because of reduced memory consumption.
  #   # But if the image is stored in a DB or generated by the gnuplot Open3.capture2 example,
  #   # Open3.capture3 should be considered.
  #   #
  #   image = File.read("/usr/share/openclipart/png/animals/mammals/sheep-md-v0.1.png", :binmode=>true)
  #   thumbnail, err, s = Open3.capture3("convert -thumbnail 80 png:- png:-", :stdin_data=>image, :binmode=>true)
  #   if s.success?
  #     STDOUT.binmode; print thumbnail
  #   end
  #
  def capture3(*cmd)
    if Hash === cmd.last
      opts = cmd.pop.dup
    else
      opts = {}
    end

stdin_data = opts.delete(:stdin_data) || ''
    binmode = opts.delete(:binmode)

popen3(*cmd, opts) {|i, o, e, t|
      if binmode
        i.binmode
        o.binmode
        e.binmode
      end
      out_reader = Thread.new { o.read }
      err_reader = Thread.new { e.read }
      begin
        if stdin_data.respond_to? :readpartial
          IO.copy_stream(stdin_data, i)
        else
          i.write stdin_data
        end
      rescue Errno::EPIPE
      end
      i.close
      [out_reader.value, err_reader.value, t.value]
    }
  end
  module_function :capture3

# Open3.capture2 captures the standard output of a command.
  #
  #   stdout_str, status = Open3.capture2([env,] cmd... [, opts])
  #
  # The arguments env, cmd and opts are passed to Open3.popen3 except
  # <code>opts[:stdin_data]</code> and <code>opts[:binmode]</code>.  See Process.spawn.
  #
  # If <code>opts[:stdin_data]</code> is specified, it is sent to the command's standard input.
  #
  # If <code>opts[:binmode]</code> is true, internal pipes are set to binary mode.
  #
  # Example:
  #
  #   # factor is a command for integer factorization.
  #   o, s = Open3.capture2("factor", :stdin_data=>"42")
  #   p o #=> "42: 2 3 7\n"
  #
  #   # generate x**2 graph in png using gnuplot.
  #   gnuplot_commands = <<"End"
  #     set terminal png
  #     plot x**2, "-" with lines
  #     1 14
  #     2 1
  #     3 8
  #     4 5
  #     e
  #   End
  #   image, s = Open3.capture2("gnuplot", :stdin_data=>gnuplot_commands, :binmode=>true)
  #
  def capture2(*cmd)
    if Hash === cmd.last
      opts = cmd.pop.dup
    else
      opts = {}
    end

stdin_data = opts.delete(:stdin_data)
    binmode = opts.delete(:binmode)

popen2(*cmd, opts) {|i, o, t|
      if binmode
        i.binmode
        o.binmode
      end
      out_reader = Thread.new { o.read }
      if stdin_data
        begin
          if stdin_data.respond_to? :readpartial
            IO.copy_stream(stdin_data, i)
          else
            i.write stdin_data
          end
        rescue Errno::EPIPE
        end
      end
      i.close
      [out_reader.value, t.value]
    }
  end
  module_function :capture2

# Open3.capture2e captures the standard output and the standard error of a command.
  #
  #   stdout_and_stderr_str, status = Open3.capture2e([env,] cmd... [, opts])
  #
  # The arguments env, cmd and opts are passed to Open3.popen3 except
  # <code>opts[:stdin_data]</code> and <code>opts[:binmode]</code>.  See Process.spawn.
  #
  # If <code>opts[:stdin_data]</code> is specified, it is sent to the command's standard input.
  #
  # If <code>opts[:binmode]</code> is true, internal pipes are set to binary mode.
  #
  # Example:
  #
  #   # capture make log
  #   make_log, s = Open3.capture2e("make")
  #
  def capture2e(*cmd)
    if Hash === cmd.last
      opts = cmd.pop.dup
    else
      opts = {}
    end

stdin_data = opts.delete(:stdin_data)
    binmode = opts.delete(:binmode)

popen2e(*cmd, opts) {|i, oe, t|
      if binmode
        i.binmode
        oe.binmode
      end
      outerr_reader = Thread.new { oe.read }
      if stdin_data
        begin
          if stdin_data.respond_to? :readpartial
            IO.copy_stream(stdin_data, i)
          else
            i.write stdin_data
          end
        rescue Errno::EPIPE
        end
      end
      i.close
      [outerr_reader.value, t.value]
    }
  end
  module_function :capture2e

# Open3.pipeline_rw starts a list of commands as a pipeline with pipes
  # which connect to stdin of the first command and stdout of the last command.
  #
  #   Open3.pipeline_rw(cmd1, cmd2, ... [, opts]) {|first_stdin, last_stdout, wait_threads|
  #     ...
  #   }
  #
  #   first_stdin, last_stdout, wait_threads = Open3.pipeline_rw(cmd1, cmd2, ... [, opts])
  #   ...
  #   first_stdin.close
  #   last_stdout.close
  #
  # Each cmd is a string or an array.
  # If it is an array, the elements are passed to Process.spawn.
  #
  #   cmd:
  #     commandline                              command line string which is passed to a shell
  #     [env, commandline, opts]                 command line string which is passed to a shell
  #     [env, cmdname, arg1, ..., opts]          command name and one or more arguments (no shell)
  #     [env, [cmdname, argv0], arg1, ..., opts] command name and arguments including argv[0] (no shell)
  #
  #   Note that env and opts are optional, as for Process.spawn.
  #
  # The options to pass to Process.spawn are constructed by merging
  # +opts+, the last hash element of the array, and
  # specifications for the pipes between each of the commands.
  #
  # Example:
  #
  #   Open3.pipeline_rw("tr -dc A-Za-z", "wc -c") {|i, o, ts|
  #     i.puts "All persons more than a mile high to leave the court."
  #     i.close
  #     p o.gets #=> "42\n"
  #   }
  #
  #   Open3.pipeline_rw("sort", "cat -n") {|stdin, stdout, wait_thrs|
  #     stdin.puts "foo"
  #     stdin.puts "bar"
  #     stdin.puts "baz"
  #     stdin.close     # send EOF to sort.
  #     p stdout.read   #=> "     1\tbar\n     2\tbaz\n     3\tfoo\n"
  #   }
  def pipeline_rw(*cmds, &block)
    if Hash === cmds.last
      opts = cmds.pop.dup
    else
      opts = {}
    end

in_r, in_w = IO.pipe
    opts[:in] = in_r
    in_w.sync = true

out_r, out_w = IO.pipe
    opts[:out] = out_w

pipeline_run(cmds, opts, [in_r, out_w], [in_w, out_r], &block)
  end
  module_function :pipeline_rw

# Open3.pipeline_r starts a list of commands as a pipeline with a pipe
  # which connects to stdout of the last command.
  #
  #   Open3.pipeline_r(cmd1, cmd2, ... [, opts]) {|last_stdout, wait_threads|
  #     ...
  #   }
  #
  #   last_stdout, wait_threads = Open3.pipeline_r(cmd1, cmd2, ... [, opts])
  #   ...
  #   last_stdout.close
  #
  # Each cmd is a string or an array.
  # If it is an array, the elements are passed to Process.spawn.
  #
  #   cmd:
  #     commandline                              command line string which is passed to a shell
  #     [env, commandline, opts]                 command line string which is passed to a shell
  #     [env, cmdname, arg1, ..., opts]          command name and one or more arguments (no shell)
  #     [env, [cmdname, argv0], arg1, ..., opts] command name and arguments including argv[0] (no shell)
  #
  #   Note that env and opts are optional, as for Process.spawn.
  #
  # Example:
  #
  #   Open3.pipeline_r("zcat /var/log/apache2/access.log.*.gz",
  #                    [{"LANG"=>"C"}, "grep", "GET /favicon.ico"],
  #                    "logresolve") {|o, ts|
  #     o.each_line {|line|
  #       ...
  #     }
  #   }
  #
  #   Open3.pipeline_r("yes", "head -10") {|o, ts|
  #     p o.read      #=> "y\ny\ny\ny\ny\ny\ny\ny\ny\ny\n"
  #     p ts[0].value #=> #<Process::Status: pid 24910 SIGPIPE (signal 13)>
  #     p ts[1].value #=> #<Process::Status: pid 24913 exit 0>
  #   }
  #
  def pipeline_r(*cmds, &block)
    if Hash === cmds.last
      opts = cmds.pop.dup
    else
      opts = {}
    end

out_r, out_w = IO.pipe
    opts[:out] = out_w

pipeline_run(cmds, opts, [out_w], [out_r], &block)
  end
  module_function :pipeline_r

# Open3.pipeline_w starts a list of commands as a pipeline with a pipe
  # which connects to stdin of the first command.
  #
  #   Open3.pipeline_w(cmd1, cmd2, ... [, opts]) {|first_stdin, wait_threads|
  #     ...
  #   }
  #
  #   first_stdin, wait_threads = Open3.pipeline_w(cmd1, cmd2, ... [, opts])
  #   ...
  #   first_stdin.close
  #
  # Each cmd is a string or an array.
  # If it is an array, the elements are passed to Process.spawn.
  #
  #   cmd:
  #     commandline                              command line string which is passed to a shell
  #     [env, commandline, opts]                 command line string which is passed to a shell
  #     [env, cmdname, arg1, ..., opts]          command name and one or more arguments (no shell)
  #     [env, [cmdname, argv0], arg1, ..., opts] command name and arguments including argv[0] (no shell)
  #
  #   Note that env and opts are optional, as for Process.spawn.
  #
  # Example:
  #
  #   Open3.pipeline_w("bzip2 -c", :out=>"/tmp/hello.bz2") {|i, ts|
  #     i.puts "hello"
  #   }
  #
  def pipeline_w(*cmds, &block)
    if Hash === cmds.last
      opts = cmds.pop.dup
    else
      opts = {}
    end

in_r, in_w = IO.pipe
    opts[:in] = in_r
    in_w.sync = true

pipeline_run(cmds, opts, [in_r], [in_w], &block)
  end
  module_function :pipeline_w

# Open3.pipeline_start starts a list of commands as a pipeline.
  # No pipes are created for stdin of the first command and
  # stdout of the last command.
  #
  #   Open3.pipeline_start(cmd1, cmd2, ... [, opts]) {|wait_threads|
  #     ...
  #   }
  #
  #   wait_threads = Open3.pipeline_start(cmd1, cmd2, ... [, opts])
  #   ...
  #
  # Each cmd is a string or an array.
  # If it is an array, the elements are passed to Process.spawn.
  #
  #   cmd:
  #     commandline                              command line string which is passed to a shell
  #     [env, commandline, opts]                 command line string which is passed to a shell
  #     [env, cmdname, arg1, ..., opts]          command name and one or more arguments (no shell)
  #     [env, [cmdname, argv0], arg1, ..., opts] command name and arguments including argv[0] (no shell)
  #
  #   Note that env and opts are optional, as for Process.spawn.
  #
  # Example:
  #
  #   # Run xeyes in 10 seconds.
  #   Open3.pipeline_start("xeyes") {|ts|
  #     sleep 10
  #     t = ts[0]
  #     Process.kill("TERM", t.pid)
  #     p t.value #=> #<Process::Status: pid 911 SIGTERM (signal 15)>
  #   }
  #
  #   # Convert pdf to ps and send it to a printer.
  #   # Collect error message of pdftops and lpr.
  #   pdf_file = "paper.pdf"
  #   printer = "printer-name"
  #   err_r, err_w = IO.pipe
  #   Open3.pipeline_start(["pdftops", pdf_file, "-"],
  #                        ["lpr", "-P#{printer}"],
  #                        :err=>err_w) {|ts|
  #     err_w.close
  #     p err_r.read # error messages of pdftops and lpr.
  #   }
  #
  def pipeline_start(*cmds, &block)
    if Hash === cmds.last
      opts = cmds.pop.dup
    else
      opts = {}
    end

if block
      pipeline_run(cmds, opts, [], [], &block)
    else
      ts, = pipeline_run(cmds, opts, [], [])
      ts
    end
  end
  module_function :pipeline_start

# Open3.pipeline starts a list of commands as a pipeline.
  # It waits for the completion of the commands.
  # No pipes are created for stdin of the first command and
  # stdout of the last command.
  #
  #   status_list = Open3.pipeline(cmd1, cmd2, ... [, opts])
  #
  # Each cmd is a string or an array.
  # If it is an array, the elements are passed to Process.spawn.
  #
  #   cmd:
  #     commandline                              command line string which is passed to a shell
  #     [env, commandline, opts]                 command line string which is passed to a shell
  #     [env, cmdname, arg1, ..., opts]          command name and one or more arguments (no shell)
  #     [env, [cmdname, argv0], arg1, ..., opts] command name and arguments including argv[0] (no shell)
  #
  #   Note that env and opts are optional, as Process.spawn.
  #
  # Example:
  #
  #   fname = "/usr/share/man/man1/ruby.1.gz"
  #   p Open3.pipeline(["zcat", fname], "nroff -man", "less")
  #   #=> [#<Process::Status: pid 11817 exit 0>,
  #   #    #<Process::Status: pid 11820 exit 0>,
  #   #    #<Process::Status: pid 11828 exit 0>]
  #
  #   fname = "/usr/share/man/man1/ls.1.gz"
  #   Open3.pipeline(["zcat", fname], "nroff -man", "colcrt")
  #
  #   # convert PDF to PS and send to a printer by lpr
  #   pdf_file = "paper.pdf"
  #   printer = "printer-name"
  #   Open3.pipeline(["pdftops", pdf_file, "-"],
  #                  ["lpr", "-P#{printer}"])
  #
  #   # count lines
  #   Open3.pipeline("sort", "uniq -c", :in=>"names.txt", :out=>"count")
  #
  #   # cyclic pipeline
  #   r,w = IO.pipe
  #   w.print "ibase=14\n10\n"
  #   Open3.pipeline("bc", "tee /dev/tty", :in=>r, :out=>w)
  #   #=> 14
  #   #   18
  #   #   22
  #   #   30
  #   #   42
  #   #   58
  #   #   78
  #   #   106
  #   #   202
  #
  def pipeline(*cmds)
    if Hash === cmds.last
      opts = cmds.pop.dup
    else
      opts = {}
    end

pipeline_run(cmds, opts, [], []) {|ts|
      ts.map(&:value)
    }
  end
  module_function :pipeline

def pipeline_run(cmds, pipeline_opts, child_io, parent_io) # :nodoc:
    if cmds.empty?
      raise ArgumentError, "no commands"
    end

opts_base = pipeline_opts.dup
    opts_base.delete :in
    opts_base.delete :out

wait_thrs = []
    r = nil
    cmds.each_with_index {|cmd, i|
      cmd_opts = opts_base.dup
      if String === cmd
        cmd = [cmd]
      else
        cmd_opts.update cmd.pop if Hash === cmd.last
      end
      if i == 0
        if !cmd_opts.include?(:in)
          if pipeline_opts.include?(:in)
            cmd_opts[:in] = pipeline_opts[:in]
          end
        end
      else
        cmd_opts[:in] = r
      end
      if i != cmds.length - 1
        r2, w2 = IO.pipe
        cmd_opts[:out] = w2
      else
        if !cmd_opts.include?(:out)
          if pipeline_opts.include?(:out)
            cmd_opts[:out] = pipeline_opts[:out]
          end
        end
      end
      pid = spawn(*cmd, cmd_opts)
      wait_thrs << Process.detach(pid)
      r&.close
      w2&.close
      r = r2
    }
    result = parent_io + [wait_thrs]
    child_io.each(&:close)
    if defined? yield
      begin
        return yield(*result)
      ensure
        parent_io.each(&:close)
        wait_thrs.each(&:join)
      end
    end
    result
  end
  module_function :pipeline_run
  class << self
    private :pipeline_run
  end

end

cmd: