Troubleshooting Quicken 2002: Multiple User Access

Yesterday we noted that Quicken Deluxe 2002 allows mutiple users to simultaneously access a data file causing damage to the resource fork and other problems. The problem may not be specific to Quicken, instead relating to a problem with OS X's handling of file status flags. John McNamee writes:

"OS X does not have a mechanism to lock users out of a data file when it is in use while OS 9 provides much more protection in that regard. I believe two people could even edit the same record at the same time. It has to do with a file status flag that Mac OS 9 has and OS X does not."

Some developers have chosen to implement a "lock file," which will cause a program to check for status when it opens the file. MYOB's AccountEdge creates a lock file so that the data file can’t be opened by another user when one is using it. The program looks to see if there is an associated lock file with the data file before opening it and it will not open if the lock file is present. When users close the file or quit the program, the lock file is then deleted so another user can access it.