> 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
