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class method
Open3.capture3
capture3(*cmd)
lib/open3.rb
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# File tmp/rubies/ruby-3.1.3/lib/open3.rb, line 280
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
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 opts[:stdin_data] and opts[:binmode]. See Process.spawn.
If opts[:stdin_data] is specified, it is sent to the command’s standard input.
If opts[:binmode] is true, internal pipes are set to binary mode.
Examples:
Example
# 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