| Class | -MCollective::Shell | -
| In: | -
-
- lib/mcollective/shell.rb
-
- - |
-
| Parent: | -- Object - | -
-Wrapper around systemu that handles executing of system commands in a way -that makes stdout, stderr and status available. Supports timeouts and sets -a default sane environment. -
-
- s = Shell.new("date", opts)
- s.runcommand
- puts s.stdout
- puts s.stderr
- puts s.status.exitstatus
-
--Options hash can have: -
-- cwd - the working directory the command will be run from - stdin - a string that will be sent to stdin of the program - stdout - a variable that will receive stdout, must support << - stderr - a variable that will receive stdin, must support << - environment - the shell environment, defaults to include LC_ALL=C - set to nil to clear the environment even of LC_ALL -- -
| command | -[R] | -- |
| cwd | -[R] | -- |
| environment | -[R] | -- |
| status | -[R] | -- |
| stderr | -[R] | -- |
| stdin | -[R] | -- |
| stdout | -[R] | -- |
- # File lib/mcollective/shell.rb, line 24 -24: def initialize(command, options={}) -25: @environment = {"LC_ALL" => "C"} -26: @command = command -27: @status = nil -28: @stdout = "" -29: @stderr = "" -30: @stdin = nil -31: @cwd = Dir.tmpdir -32: -33: options.each do |opt, val| -34: case opt.to_s -35: when "stdout" -36: raise "stdout should support <<" unless val.respond_to?("<<") -37: @stdout = val -38: -39: when "stderr" -40: raise "stderr should support <<" unless val.respond_to?("<<") -41: @stderr = val -42: -43: when "stdin" -44: raise "stdin should be a String" unless val.is_a?(String) -45: @stdin = val -46: -47: when "cwd" -48: raise "Directory #{val} does not exist" unless File.directory?(val) -49: @cwd = val -50: -51: when "environment" -52: if val.nil? -53: @environment = {} -54: else -55: @environment.merge!(val.dup) -56: end -57: end -58: end -59: end --
-Actually does the systemu call passing in the correct environment, stdout -and stderr -
- -- # File lib/mcollective/shell.rb, line 62 -62: def runcommand -63: opts = {"env" => @environment, -64: "stdout" => @stdout, -65: "stderr" => @stderr, -66: "cwd" => @cwd} -67: -68: opts["stdin"] = @stdin if @stdin -69: -70: # Check if the parent thread is alive. If it should die, -71: # and the process spawned by systemu is still alive, -72: # fire off a blocking waitpid and wait for the process to -73: # finish so that we can avoid zombies. -74: thread = Thread.current -75: @status = systemu(@command, opts) do |cid| -76: begin -77: while(thread.alive?) -78: sleep 0.1 -79: end -80: -81: Process.waitpid(cid) if Process.getpgid(cid) -82: rescue SystemExit -83: rescue Errno::ESRCH -84: rescue Errno::ECHILD -85: rescue Exception => e -86: Log.info("Unexpected exception received while waiting for child process: #{e.class}: #{e}") -87: end -88: end -89: end --