#
# = 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 the
# child process when running another program.
# You can specify various attributes, redirections, current directory, etc., of
# the program as 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 and don't wait
# - Open3.pipeline : run a pipeline and wait
#
module Open3
# Open stdin, stdout, and stderr streams and start external executable.
# In addition, a thread for waiting the started process is noticed.
# The thread has a pid method and 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 +cmd...+ is passed to Process.spawn.
# So a commandline string and 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 the termination of the process.
# The block form also waits the process when it returns.
#
# Closing stdin, stdout and stderr does not wait the process.
#
# You should be careful to avoid deadlocks.
# Since pipes are fixed length buffer,
# Open3.popen3("prog") {|i, o, e, t| o.read } deadlocks if
# the program generates many output on stderr.
# You should be read stdout and stderr simultaneously (using thread or IO.select).
# However if you don't need stderr output, Open3.popen2 can be used.
# If merged stdout and stderr output is not a problem, you can use Open3.popen2e.
# If you really needs 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 similer to Open3.popen3 except it doesn't make 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 similer to Open3.popen3 except 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 {|io| io.close }
result = [*parent_io, wait_thr]
if defined? yield
begin
return yield(*result)
ensure
parent_io.each{|io| io.close unless io.closed?}
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
# 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.
#
# Example:
#
# # dot is a command of graphviz.
# graph = <<'End'
# digraph g {
# a -> b
# }
# End
# layouted_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 thumnail image using the convert command of ImageMagick.
# # However, if the image stored really in a file,
# # system("convert", "-thumbnail", "80", "png:#{filename}", "png:-") is better
# # because memory consumption.
# # But if the image is stored in a DB or generated by gnuplot Open3.capture2 example,
# # Open3.capture3 is considerable.
# #
# image = File.read("/usr/share/openclipart/png/animals/mammals/sheep-md-v0.1.png", :binmode=>true)
# thumnail, err, s = Open3.capture3("convert -thumbnail 80 png:- png:-", :stdin_data=>image, :binmode=>true)
# if s.success?
# STDOUT.binmode; print thumnail
# 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 }
i.write stdin_data
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
# 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.
#
# 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 }
i.write stdin_data
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
# 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.
#
# 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 }
i.write stdin_data
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 connects 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 Process.spawn.
#
# The option to pass Process.spawn is constructed by merging
# +opts+, the last hash element of the array and
# specification for the pipe between each 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 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 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 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 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 pipe made 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 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 the finish of the commands.
# No pipe made 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 {|t| t.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 if r
w2.close if w2
r = r2
}
result = parent_io + [wait_thrs]
child_io.each {|io| io.close }
if defined? yield
begin
return yield(*result)
ensure
parent_io.each{|io| io.close unless io.closed?}
wait_thrs.each {|t| t.join }
end
end
result
end
module_function :pipeline_run
class << self
private :pipeline_run
end
end
if $0 == __FILE__
a = Open3.popen3("nroff -man")
Thread.start do
while line = gets
a[0].print line
end
a[0].close
end
while line = a[1].gets
print ":", line
end
end