thank you a lot for the feedback. It is not only Windows using advisory locking and aborting other reads, it is the same with Mac OS X using AFP volumes or a Samba CIFS volume mount on a Linux client. I understand the problem and consider to add a ".backup" command to the sqlite shell to backup a running database.
I still believe it is an good idea to move the lock range outside of the file range e.g. 0xffffffffffff0000. Word/Excel using as well a locking in high area for simple interprocess communication about the current Word/Excel file.
Helmut Tschemernjak
D. Richard Hipp wrote:
On Mon, 2005-05-16 at 15:58 +0200, Helmut Tschemernjak wrote:
thank you for the info, another possible problem is that I cannot backup the database e.g. "begin exclusive" and copy the entire DB file while the main server app is still running. The copy aborts at offset 1GB.
This is only a problem on windows. (Unix lets you make a copy of the file even though it is locked - unix got this part right.)
A easy work-around would be to write a custom "copy" program that ignored bytes 1GiB through 1Gib+510.
