"Permission Denied" error

[Boaz Bezborodko]

I've gotten this error a couple of times, but this is the first time I 
know what was running that probably caused it.

I was running a long job that was processing payments on a few thousand 
invoices at once.  (One check for about 9,000 invoices and can take as 
much as an hour to run.)  As it processes it accesses a control record 
for invoice numbers and does a protected lookup. While I was running 
this someone else start running a billing operation that generates 
invoices and accesses this same record. Both access the record in 
protected mode and I was seeing where each program was occasionally 
waiting on the other for the record to be unlocked.   I got the error 
"Permission Denied" about the time that I think the billing program 
finished.

In the programing I lookup 'fln -p' each time I want to get a number, 
read the number, increment it, and then use 'WRITE fln' to release the 
lock like this:
lookup inv = invno  r=("1")   -ep
com(5)=inv(167) ; inv(167)=com(5)+"1" ; WRITE inv

When a program ends it will close the file.  Is there something in the 
process that allows Filepro to return deny access instead of returning a 
record locked response such that this error occurs? Even if this is a 
relative rarity, it still happens to me quite often when I happen to 
have these checks paying off large numbers of invoices.

I'm running Windows Filepro 5.6.10R9 to a Samba file server.