Get the configuration of the current server.
If there is no current server, this returns the default configuration. See current_server and DRbServer::make_config.
Get the configuration of the current server.
If there is no current server, this returns the default configuration. See current_server and DRbServer::make_config.
Get the front object of the current server.
This raises a DRbServerNotFound error if there is no current server. See current_server.
Get the front object of the current server.
This raises a DRbServerNotFound error if there is no current server. See current_server.
Returns true if new is newer than all old_list. Non-existent files are older than any file.
FileUtils.uptodate?('hello.o', %w(hello.c hello.h)) or \ system 'make hello.o'
Returns true if new is newer than all old_list. Non-existent files are older than any file.
FileUtils.uptodate?('hello.o', %w(hello.c hello.h)) or \ system 'make hello.o'
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.
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.
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 #=> "*" }
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 #=> "*" }
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
}
}
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
}
}
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:
# 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
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:
# 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
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)