Tip #4 Multi-user filePro developers

To do a check that all the records that are written to in processing have been properly locked, use the PFCHECKLOCK environment variable.

From the filePro Main Menu, press <?> - filePro Directory, then select <F6>-Configuration Editor ( your keystroke may vary, look at the bottom of the screen for yours). Then add on a blank line the PFCHECKLOCK entry.

Variable	Value	Note
PFCHECKLOCK	ON	ON or OFF

Or put it only in your environment at the prompt. (Use this on a live system, please.)

PFCHECKLOCK=ON;export PFCHECKLOCK	(Unix)
set PFCHECKLOCK=ON	(DOS NETWORK)

Then run your application like the end user will use it. If any postings or changes are made to records that are not locked, a box will appear on the screen with all the information you need to locate the processing cell and fix it. This is great tool to apply to old applications that were written without the skills we have developed over the years. Or use it to make sure an application that was written as a single user system, will work multi-user. Finally, if you are experiencing any record locking problems or data loss on records that are shared, this tool will help you eliminate the unlocked record possibility.

Remember, without locking a record, if two people open a record at the same time, the last to write will overwrite any changes the first person made to the record. Two people entering an invoice for the same customer, they both try to update the YTD Sales for the customer, one invoice will not be added since the starting number they both got was the same. It could happen, and it does, especially on widely shared records like control records that might be used to assign Next Invoice Number. (duplicate numbers might be the result). This variable was added to the later versions of 4.1 and has been a valuable development tool. I think you will like it also.

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Written by Nancy Palmquist

Copyright, 1997 by Virtual Software Systems.  All rights reserved.