>I would like to pack database which use for sharing. I let program to pack every 1st of month. I would like the last user who quit program change exclusive to on automatic for using "Pack" cammand. How can we write the program to protect and check to open "Exclusive on or off" or whick command for checking the numbers of user who are using the program.
> From NO.
For that you don't need to know the number of users at the moment (2 or 10 would be same). Try a flock on tables and if succeed, turn on a flag for users that may login (ie: creation of a dummy text file could server as a fiag) then start your exclusive mode operations. If you keep a table for users in system you could only check it to see if anyone else is online too.
Cetin