# Win32/process question **URL:** \ **Category:** Ruby\ **Created:** [November 10, 2006, 6:55am UTC](https://www.ruby-forum.com/t/win32-process-question/75479 "2006-11-10T06:55:23Z")\ **Posts on this page:** 9\ **Page:** 1
**Author:** ![J-Van](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/j/bc8723/32.png) [@J-Van](https://www.ruby-forum.com/u/J-Van)\ **Post date:** [November 10, 2006, 6:55am UTC](https://www.ruby-forum.com/t/win32-process-question/75479/1 "2006-11-10T06:55:23Z")
On Windows XP, Ruby 1.8.5: # start notepad irb(main):003:0\> info = Process.create :app\_name =\> “notepad” =\> # # notepad running irb(main):004:0\> Process.kill 0, info.process\_id =\> [3536] # kill notepad irb(main):005:0\> Process.kill 9, info.process\_id =\> [3536] # notepad’s dead, but why doesn’t this throw an exception?! irb(main):006:0\> Process.kill 0, info.process\_id =\> [3536] Any ideas? Thanks, Joe ---
**Author:** ![J-Van](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/j/bc8723/32.png) [@J-Van](https://www.ruby-forum.com/u/J-Van)\ **Post date:** [November 10, 2006, 7:47am UTC](https://www.ruby-forum.com/t/win32-process-question/75479/2 "2006-11-10T07:47:25Z")
I guess I should note that this is after I require ‘win32/process’ (which is installed via a gem). ---
**Author:** ![J-Van](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/j/bc8723/32.png) [@J-Van](https://www.ruby-forum.com/u/J-Van)\ **Post date:** [November 10, 2006, 11:29am UTC](https://www.ruby-forum.com/t/win32-process-question/75479/3 "2006-11-10T11:29:51Z")
Hi, > > On Windows XP, Ruby 1.8.5: > > > > # kill notepad Refer to [http://msdn2.microsoft.com/fr-fr/library/ms686722.aspx](http://msdn2.microsoft.com/fr-fr/library/ms686722.aspx), “While open handles to kernel objets are closed automatically when a process terminates, the objects themselves exist until all open handles to them are closed. Therefore, an object will remain valid after a process that is using it terminates if another process has an open handle to it.” Here is the working code. irb(main):001:0\> require ‘win32/process’ =\> true irb(main):002:0\> include Windows::Handle =\> Object irb(main):003:0\> info = Process.create :app\_name=\>‘notepad’ =\> # irb(main):004:0\> Process.kill 0,info.process\_id =\> [1748] irb(main):005:0\> Process.kill 9,info.process\_id =\> [1748] irb(main):006:0\> CloseHandle(info.process\_handle) =\> true irb(main):007:0\> CloseHandle(info.thread\_handle) =\> true irb(main):008:0\> Process.kill 0,info.process\_id ProcessError: The parameter is incorrect. from c:/ruby/lib/ruby/gems/1.8/gems/win32-process-0.5.1/lib/win32/proces s.rb:156:in `kill' from c:/ruby/lib/ruby/gems/1.8/gems/win32-process-0.5.1/lib/win32/proces s.rb:132:in `each’ from c:/ruby/lib/ruby/gems/1.8/gems/win32-process-0.5.1/lib/win32/proces s.rb:132:in `kill’ from (irb):8 Regards, Park H. ---
**Author:** ![J-Van](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/j/bc8723/32.png) [@J-Van](https://www.ruby-forum.com/u/J-Van)\ **Post date:** [November 10, 2006, 7:25pm UTC](https://www.ruby-forum.com/t/win32-process-question/75479/4 "2006-11-10T19:25:08Z")
On 11/10/06, Park H. [removed\_email\_address@domain.invalid](mailto:removed_email_address@domain.invalid) wrote: > > (which is installed via a gem). > > > > > irb(main):004:0\> Process.kill 0, info.process\_id > > > Any ideas? > > > Here is the working code. > > > =\> [1748] > > > s.rb:156:in `kill' from c:/ruby/lib/ruby/gems/1.8/gems/win32-process-0.5.1/lib/win32/proces s.rb:132:in `each’ > > > from > > > c:/ruby/lib/ruby/gems/1.8/gems/win32-process-0.5.1/lib/win32/proces > > > s.rb:132:in `kill’ > > > from (irb):8 So, if I use Process.create to create a new process, and I want to know when a user closed the program, I should close the handle to the process immediately after starting it? And then Process.kill(0, ) would return an exception once the user closed the program? Joe ---
**Author:** ![J-Van](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/j/bc8723/32.png) [@J-Van](https://www.ruby-forum.com/u/J-Van)\ **Post date:** [November 11, 2006, 1:19am UTC](https://www.ruby-forum.com/t/win32-process-question/75479/5 "2006-11-11T01:19:57Z")
Hi, > From: J-Van [removed\_email\_address@domain.invalid](mailto:removed_email_address@domain.invalid) > Reply-To: removed\_email\_address@domain.invalid > To: removed\_email\_address@domain.invalid (ruby-talk ML) > Subject: Re: win32/process question > Date: Sat, 11 Nov 2006 03:24:34 +0900 > > On 11/10/06, Park H. [removed\_email\_address@domain.invalid](mailto:removed_email_address@domain.invalid) wrote: > > > Hi, … > > Here is the working code. > > =\> [1748] > > s.rb:156:in `kill’ > > process immediately after starting it? And then Process.kill(0, > > ) would return an exception once the user closed the program? > > Joe You cannot close the hanle if the process is still alive. You can use WaitForSingleObject or Process.waitpid to wait until child process exits like this: require ‘win32/process’ include Windows::Handle info = Process.create :app\_name=\>‘notepad’ Process.waitpid(info.process\_id) CloseHandle(info.process\_handle) CloseHandle(info.thread\_handle) Regards, Park H. ---
**Author:** ![J-Van](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/j/bc8723/32.png) [@J-Van](https://www.ruby-forum.com/u/J-Van)\ **Post date:** [November 11, 2006, 1:29am UTC](https://www.ruby-forum.com/t/win32-process-question/75479/6 "2006-11-11T01:29:58Z")
On 11/10/06, Park H. [removed\_email\_address@domain.invalid](mailto:removed_email_address@domain.invalid) wrote: > > > using > > > process > > > ProcessError: The parameter is incorrect. > > require ‘win32/process’ > include Windows::Handle > info = Process.create :app\_name=\>‘notepad’ > Process.waitpid(info.process\_id) > CloseHandle(info.process\_handle) > CloseHandle(info.thread\_handle) If I use Process.waitpid in a thread, all the other threads seem to block until the process that I’m waiting for stops. I’m writing a program that runs on a windows machine that listens for requests to start and kill programs. It needs to be able to run and kill multiple programs and needs to be able to monitor the programs that it has started to make sure that they are still running. If Process.waitpid makes the whole Ruby process hang, that’s no good. Joe ---
**Author:** ![J-Van](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/j/bc8723/32.png) [@J-Van](https://www.ruby-forum.com/u/J-Van)\ **Post date:** [November 10, 2006, 7:23pm UTC](https://www.ruby-forum.com/t/win32-process-question/75479/7 "2006-11-10T19:23:07Z")
On 11/10/06, Park H. [removed\_email\_address@domain.invalid](mailto:removed_email_address@domain.invalid) wrote: > > (which is installed via a gem). > > > > > irb(main):004:0\> Process.kill 0, info.process\_id > > > Any ideas? > > > Here is the working code. > > > =\> [1748] > > > s.rb:156:in `kill' from c:/ruby/lib/ruby/gems/1.8/gems/win32-process-0.5.1/lib/win32/proces s.rb:132:in `each’ > > > from > > > c:/ruby/lib/ruby/gems/1.8/gems/win32-process-0.5.1/lib/win32/proces > > > s.rb:132:in `kill’ > > > from (irb):8 Fantastic, thanks! Joe ---
**Author:** ![J-Van](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/j/bc8723/32.png) [@J-Van](https://www.ruby-forum.com/u/J-Van)\ **Post date:** [November 11, 2006, 2:08am UTC](https://www.ruby-forum.com/t/win32-process-question/75479/8 "2006-11-11T02:08:03Z")
> From: J-Van [removed\_email\_address@domain.invalid](mailto:removed_email_address@domain.invalid) > Reply-To: removed\_email\_address@domain.invalid > To: removed\_email\_address@domain.invalid (ruby-talk ML) > Subject: Re: win32/process question > Date: Sat, 11 Nov 2006 09:29:10 +0900 … > Joe If you don’t want blocking, try WaitForSingleObect like this: require ‘win32/process’ include Windows::Handle include Windows::Synchronize info = Process.create :app\_name=\>‘notepad’ begin i = WaitForSingleObject(info.process\_handle,10) if i==WAIT\_OBJECT\_0 CloseHandle(info.process\_handle) CloseHandle(info.thread\_handle) end # do something end while i==WAIT\_TIMEOUT Regards, Park H. ---
**Author:** ![J-Van](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/j/bc8723/32.png) [@J-Van](https://www.ruby-forum.com/u/J-Van)\ **Post date:** [November 11, 2006, 2:30am UTC](https://www.ruby-forum.com/t/win32-process-question/75479/9 "2006-11-11T02:30:09Z")
On 11/10/06, Park H. [removed\_email\_address@domain.invalid](mailto:removed_email_address@domain.invalid) wrote: > > > > require ‘win32/process’ > end > > # do something > > end while i==WAIT\_TIMEOUT Thanks – I’ll try that. I’m not exactly sure what those functions do though. 🙂 Joe