Re: [daemon] Unable to read tomcat.pid file created by Tomcat process
On Nov 11, 2014, at 7:44 PM, Bernd Eckenfels e...@zusammenkunft.net wrote: Am Tue, 11 Nov 2014 00:09:57 -0500 schrieb Anil Ambati aamb...@us.ibm.com: Why does the Tomcat server keep the PID file locked, preventing other processes to even read the file? Is there a work around or solution for this problem? I think the reason for that is, that you can this way detect if the process is still running: if it is locked, then it is running. Assuming that the pid file is created in the native code of procrun, then this could be solved by using the fine-grained sharing options of the Win32 API CreateFile (which is used to both create and open files). Specifically, procrun could call CreateFile so as to open the file in a mode where other processes can read the file but not write to it by passing FILE_SHARE_READ for the dwShareMode parameter. This would allow other processes to read the file by opening for read-only access, and it would also allow another process to test if the procrun process is still running by opening with write access. Of course this makes it hard to read the file. To work around this I guess a native library is needed. (Or you execute cmd /C type file.pid). Not sure if any component offers this (might be a good addition to commons-daemon). I don’t think a native library or cmd’s type command will help here -- if the OS is enforcing exclusive access to the file, then that restriction will apply to all other processes. -Ian - To unsubscribe, e-mail: user-unsubscr...@commons.apache.org For additional commands, e-mail: user-h...@commons.apache.org
[daemon] Unable to read tomcat.pid file created by Tomcat process
I was asked to post this question in this forum. We have a requirement to read the PID file created by the Tomcat server process on Windows, but we are not able to using RandomAccessFile or FileInputStream because the file seems to be locked by the Tomcat process. Why does the Tomcat server keep the PID file locked, preventing other processes to even read the file? Is there a work around or solution for this problem? Christopher Schultz wrote this in Tomcat user forum: I took a quick look, and it looks like the PID file is being created with a file option FILE_FLAG_DELETE_ON_CLOSE which causes the OS to delete the file off the disk when all file handles are closed. So, closing the file handle will result in the PID file being deleted. This option was added because the PID file wasn't being removed if the service crashed, which kept the service from restarting (oops). https://issues.apache.org/jira/browse/DAEMON-183 It seems like an option to control what happens on startup when the PID file already exists would be a good idea. You'll have to ask the procrun folks about what the options are. It seems reasonable to be able to read the PID file, since not being able to read it makes it kind of useless other than as a lock-file (i.e. its contents are irrelevant). Regards, Anilkumar Ambati 4205 S Miami Blvd WebSphere Virtual Enterprise Development Durham, 27703-9141 Phone: +1-919-254-6152 USA Mobile: +1-919-434-5674 e-mail: aamb...@us.ibm.com You have no responsibility to live up to what other people think you ought to accomplish. -Richard Feynman (1918-1988)
Re: [daemon] Unable to read tomcat.pid file created by Tomcat process
Oops, sorry, please ignore my previous message. On Tue, Nov 11, 2014 at 10:11 AM, Gary Gregory garydgreg...@gmail.com wrote: Wrong list. You probably want https://tomcat.apache.org/lists.html#tomcat-users Gary On Tue, Nov 11, 2014 at 10:06 AM, Anil Ambati aamb...@us.ibm.com wrote: I was asked to post this question in this forum. We have a requirement to read the PID file created by the Tomcat server process on Windows, but we are not able to using RandomAccessFile or FileInputStream because the file seems to be locked by the Tomcat process. Why does the Tomcat server keep the PID file locked, preventing other processes to even read the file? Is there a work around or solution for this problem? Christopher Schultz wrote this in Tomcat user forum: I took a quick look, and it looks like the PID file is being created with a file option FILE_FLAG_DELETE_ON_CLOSE which causes the OS to delete the file off the disk when all file handles are closed. So, closing the file handle will result in the PID file being deleted. This option was added because the PID file wasn't being removed if the service crashed, which kept the service from restarting (oops). https://issues.apache.org/jira/browse/DAEMON-183 It seems like an option to control what happens on startup when the PID file already exists would be a good idea. You'll have to ask the procrun folks about what the options are. It seems reasonable to be able to read the PID file, since not being able to read it makes it kind of useless other than as a lock-file (i.e. its contents are irrelevant). Regards, -- *Anilkumar Ambati* 4205 S Miami Blvd WebSphere Virtual Enterprise Development Durham, 27703-9141 Phone: +1-919-254-6152 USA Mobile: +1-919-434-5674e-mail: aamb...@us.ibm.com -- You have no responsibility to live up to what other people think you ought to accomplish. -Richard Feynman (1918-1988) -- E-Mail: garydgreg...@gmail.com | ggreg...@apache.org Java Persistence with Hibernate, Second Edition http://www.manning.com/bauer3/ JUnit in Action, Second Edition http://www.manning.com/tahchiev/ Spring Batch in Action http://www.manning.com/templier/ Blog: http://garygregory.wordpress.com Home: http://garygregory.com/ Tweet! http://twitter.com/GaryGregory -- E-Mail: garydgreg...@gmail.com | ggreg...@apache.org Java Persistence with Hibernate, Second Edition http://www.manning.com/bauer3/ JUnit in Action, Second Edition http://www.manning.com/tahchiev/ Spring Batch in Action http://www.manning.com/templier/ Blog: http://garygregory.wordpress.com Home: http://garygregory.com/ Tweet! http://twitter.com/GaryGregory
Re: [daemon] Unable to read tomcat.pid file created by Tomcat process
So which version of [daemon] are you using? Can you try the latest and greatest. It might not matter but it'll make debugging easier for anyone on this ML. Gary On Tue, Nov 11, 2014 at 10:06 AM, Anil Ambati aamb...@us.ibm.com wrote: I was asked to post this question in this forum. We have a requirement to read the PID file created by the Tomcat server process on Windows, but we are not able to using RandomAccessFile or FileInputStream because the file seems to be locked by the Tomcat process. Why does the Tomcat server keep the PID file locked, preventing other processes to even read the file? Is there a work around or solution for this problem? Christopher Schultz wrote this in Tomcat user forum: I took a quick look, and it looks like the PID file is being created with a file option FILE_FLAG_DELETE_ON_CLOSE which causes the OS to delete the file off the disk when all file handles are closed. So, closing the file handle will result in the PID file being deleted. This option was added because the PID file wasn't being removed if the service crashed, which kept the service from restarting (oops). https://issues.apache.org/jira/browse/DAEMON-183 It seems like an option to control what happens on startup when the PID file already exists would be a good idea. You'll have to ask the procrun folks about what the options are. It seems reasonable to be able to read the PID file, since not being able to read it makes it kind of useless other than as a lock-file (i.e. its contents are irrelevant). Regards, -- *Anilkumar Ambati* 4205 S Miami Blvd WebSphere Virtual Enterprise Development Durham, 27703-9141 Phone: +1-919-254-6152 USA Mobile: +1-919-434-5674e-mail: aamb...@us.ibm.com -- You have no responsibility to live up to what other people think you ought to accomplish. -Richard Feynman (1918-1988) -- E-Mail: garydgreg...@gmail.com | ggreg...@apache.org Java Persistence with Hibernate, Second Edition http://www.manning.com/bauer3/ JUnit in Action, Second Edition http://www.manning.com/tahchiev/ Spring Batch in Action http://www.manning.com/templier/ Blog: http://garygregory.wordpress.com Home: http://garygregory.com/ Tweet! http://twitter.com/GaryGregory
Re: [daemon] Unable to read tomcat.pid file created by Tomcat process
I am using Apache Tomcat 7.0.56. I think that is the latest. Regards, Anilkumar Ambati 4205 S Miami Blvd WebSphere Virtual Enterprise Development Durham, 27703-9141 Phone: +1-919-254-6152 USA Mobile: +1-919-434-5674 e-mail: aamb...@us.ibm.com You have no responsibility to live up to what other people think you ought to accomplish. -Richard Feynman (1918-1988) From: Gary Gregory garydgreg...@gmail.com To: Commons Users List user@commons.apache.org, Date: 11/11/2014 10:18 AM Subject: Re: [daemon] Unable to read tomcat.pid file created by Tomcat process So which version of [daemon] are you using? Can you try the latest and greatest. It might not matter but it'll make debugging easier for anyone on this ML. Gary On Tue, Nov 11, 2014 at 10:06 AM, Anil Ambati aamb...@us.ibm.com wrote: I was asked to post this question in this forum. We have a requirement to read the PID file created by the Tomcat server process on Windows, but we are not able to using RandomAccessFile or FileInputStream because the file seems to be locked by the Tomcat process. Why does the Tomcat server keep the PID file locked, preventing other processes to even read the file? Is there a work around or solution for this problem? Christopher Schultz wrote this in Tomcat user forum: I took a quick look, and it looks like the PID file is being created with a file option FILE_FLAG_DELETE_ON_CLOSE which causes the OS to delete the file off the disk when all file handles are closed. So, closing the file handle will result in the PID file being deleted. This option was added because the PID file wasn't being removed if the service crashed, which kept the service from restarting (oops). https://issues.apache.org/jira/browse/DAEMON-183 It seems like an option to control what happens on startup when the PID file already exists would be a good idea. You'll have to ask the procrun folks about what the options are. It seems reasonable to be able to read the PID file, since not being able to read it makes it kind of useless other than as a lock-file (i.e. its contents are irrelevant). Regards, -- *Anilkumar Ambati* 4205 S Miami Blvd WebSphere Virtual Enterprise Development Durham, 27703-9141 Phone: +1-919-254-6152 USA Mobile: +1-919-434-5674e-mail: aamb...@us.ibm.com -- You have no responsibility to live up to what other people think you ought to accomplish. -Richard Feynman (1918-1988) -- E-Mail: garydgreg...@gmail.com | ggreg...@apache.org Java Persistence with Hibernate, Second Edition http://www.manning.com/bauer3/ JUnit in Action, Second Edition http://www.manning.com/tahchiev/ Spring Batch in Action http://www.manning.com/templier/ Blog: http://garygregory.wordpress.com Home: http://garygregory.com/ Tweet! http://twitter.com/GaryGregory
Re: [daemon] Unable to read tomcat.pid file created by Tomcat process
Sorry, I meant what version of Commons Daemon. Gary On Tue, Nov 11, 2014 at 11:37 AM, Anil Ambati aamb...@us.ibm.com wrote: I am using Apache Tomcat 7.0.56. I think that is the latest. Regards, -- *Anilkumar Ambati* 4205 S Miami Blvd WebSphere Virtual Enterprise Development Durham, 27703-9141 Phone: +1-919-254-6152 USA Mobile: +1-919-434-5674e-mail: aamb...@us.ibm.com -- You have no responsibility to live up to what other people think you ought to accomplish. -Richard Feynman (1918-1988) From: Gary Gregory garydgreg...@gmail.com To: Commons Users List user@commons.apache.org, Date: 11/11/2014 10:18 AM Subject: Re: [daemon] Unable to read tomcat.pid file created by Tomcat process -- So which version of [daemon] are you using? Can you try the latest and greatest. It might not matter but it'll make debugging easier for anyone on this ML. Gary On Tue, Nov 11, 2014 at 10:06 AM, Anil Ambati aamb...@us.ibm.com wrote: I was asked to post this question in this forum. We have a requirement to read the PID file created by the Tomcat server process on Windows, but we are not able to using RandomAccessFile or FileInputStream because the file seems to be locked by the Tomcat process. Why does the Tomcat server keep the PID file locked, preventing other processes to even read the file? Is there a work around or solution for this problem? Christopher Schultz wrote this in Tomcat user forum: I took a quick look, and it looks like the PID file is being created with a file option FILE_FLAG_DELETE_ON_CLOSE which causes the OS to delete the file off the disk when all file handles are closed. So, closing the file handle will result in the PID file being deleted. This option was added because the PID file wasn't being removed if the service crashed, which kept the service from restarting (oops). https://issues.apache.org/jira/browse/DAEMON-183 It seems like an option to control what happens on startup when the PID file already exists would be a good idea. You'll have to ask the procrun folks about what the options are. It seems reasonable to be able to read the PID file, since not being able to read it makes it kind of useless other than as a lock-file (i.e. its contents are irrelevant). Regards, -- *Anilkumar Ambati* 4205 S Miami Blvd WebSphere Virtual Enterprise Development Durham, 27703-9141 Phone: +1-919-254-6152 USA Mobile: +1-919-434-5674e-mail: aamb...@us.ibm.com -- You have no responsibility to live up to what other people think you ought to accomplish. -Richard Feynman (1918-1988) -- E-Mail: garydgreg...@gmail.com | ggreg...@apache.org Java Persistence with Hibernate, Second Edition http://www.manning.com/bauer3/ JUnit in Action, Second Edition http://www.manning.com/tahchiev/ Spring Batch in Action http://www.manning.com/templier/ Blog: http://garygregory.wordpress.com Home: http://garygregory.com/ Tweet! http://twitter.com/GaryGregory -- E-Mail: garydgreg...@gmail.com | ggreg...@apache.org Java Persistence with Hibernate, Second Edition http://www.manning.com/bauer3/ JUnit in Action, Second Edition http://www.manning.com/tahchiev/ Spring Batch in Action http://www.manning.com/templier/ Blog: http://garygregory.wordpress.com Home: http://garygregory.com/ Tweet! http://twitter.com/GaryGregory
Re: [daemon] Unable to read tomcat.pid file created by Tomcat process
On 11/11/2014 16:47, Gary Gregory wrote: Sorry, I meant what version of Commons Daemon. It is the latest release. 1.0.15. Mark Gary On Tue, Nov 11, 2014 at 11:37 AM, Anil Ambati aamb...@us.ibm.com wrote: I am using Apache Tomcat 7.0.56. I think that is the latest. Regards, -- *Anilkumar Ambati* 4205 S Miami Blvd WebSphere Virtual Enterprise Development Durham, 27703-9141 Phone: +1-919-254-6152 USA Mobile: +1-919-434-5674e-mail: aamb...@us.ibm.com -- You have no responsibility to live up to what other people think you ought to accomplish. -Richard Feynman (1918-1988) From: Gary Gregory garydgreg...@gmail.com To: Commons Users List user@commons.apache.org, Date: 11/11/2014 10:18 AM Subject: Re: [daemon] Unable to read tomcat.pid file created by Tomcat process -- So which version of [daemon] are you using? Can you try the latest and greatest. It might not matter but it'll make debugging easier for anyone on this ML. Gary On Tue, Nov 11, 2014 at 10:06 AM, Anil Ambati aamb...@us.ibm.com wrote: I was asked to post this question in this forum. We have a requirement to read the PID file created by the Tomcat server process on Windows, but we are not able to using RandomAccessFile or FileInputStream because the file seems to be locked by the Tomcat process. Why does the Tomcat server keep the PID file locked, preventing other processes to even read the file? Is there a work around or solution for this problem? Christopher Schultz wrote this in Tomcat user forum: I took a quick look, and it looks like the PID file is being created with a file option FILE_FLAG_DELETE_ON_CLOSE which causes the OS to delete the file off the disk when all file handles are closed. So, closing the file handle will result in the PID file being deleted. This option was added because the PID file wasn't being removed if the service crashed, which kept the service from restarting (oops). https://issues.apache.org/jira/browse/DAEMON-183 It seems like an option to control what happens on startup when the PID file already exists would be a good idea. You'll have to ask the procrun folks about what the options are. It seems reasonable to be able to read the PID file, since not being able to read it makes it kind of useless other than as a lock-file (i.e. its contents are irrelevant). Regards, -- *Anilkumar Ambati* 4205 S Miami Blvd WebSphere Virtual Enterprise Development Durham, 27703-9141 Phone: +1-919-254-6152 USA Mobile: +1-919-434-5674e-mail: aamb...@us.ibm.com -- You have no responsibility to live up to what other people think you ought to accomplish. -Richard Feynman (1918-1988) -- E-Mail: garydgreg...@gmail.com | ggreg...@apache.org Java Persistence with Hibernate, Second Edition http://www.manning.com/bauer3/ JUnit in Action, Second Edition http://www.manning.com/tahchiev/ Spring Batch in Action http://www.manning.com/templier/ Blog: http://garygregory.wordpress.com Home: http://garygregory.com/ Tweet! http://twitter.com/GaryGregory - To unsubscribe, e-mail: user-unsubscr...@commons.apache.org For additional commands, e-mail: user-h...@commons.apache.org
Re: [daemon] Unable to read tomcat.pid file created by Tomcat process
Am Tue, 11 Nov 2014 00:09:57 -0500 schrieb Anil Ambati aamb...@us.ibm.com: Why does the Tomcat server keep the PID file locked, preventing other processes to even read the file? Is there a work around or solution for this problem? I think the reason for that is, that you can this way detect if the process is still running: if it is locked, then it is running. Of course this makes it hard to read the file. To work around this I guess a native library is needed. (Or you execute cmd /C type file.pid). Not sure if any component offers this (might be a good addition to commons-daemon). Gruss Bernd - To unsubscribe, e-mail: user-unsubscr...@commons.apache.org For additional commands, e-mail: user-h...@commons.apache.org
