> -----Original Message----- > From: HENRY,MARK (HP-Roseville,ex1) [mailto:[EMAIL PROTECTED]] > Sent: Tuesday, June 04, 2002 12:15 PM > To: '[EMAIL PROTECTED]' > Cc: HENRY,MARK (HP-Roseville,ex1) > Subject: avoiding 2nd process > > > All, > > Wondering what the best approach would be to the following. > > I have a script which copies files and sends mail notification > appropriately. > > I want the script to check for new source files every 15 > mins, however when > there are new files, the operation will take long enough to > the point where > a second instance of the script will start while the first is still > executing - obviously I don't want two copies running simultaneously. > My first thought would be to create a dummy file upon start > and if this > exists, a second instance wouldn't begin, then deleting the > file when the > operation is complete. > > Is there a better way of doing this?
Use a lock instead of just the presence of a file. If your script dies without removing the file, all subsequent calls are blocked until you manually remove the file. If you use a lock, the kernel will automatically release when your process ends, even if it terminates abnormally. See: <http://www.stonehenge.com/merlyn/WebTechniques/col54.html> -- To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
