Record Locking

BR 3.8 uses 31 bit locking. BR 3.9 used 30 bit locking to be compatible with CIFS / SMB products like Samba and SCO Vision. However this proved to be an unacceptable limitation because files that are greater than 1 gigabyte can get random locked records for no apparent reason.

As of release levels 3.92i/4.02i/4.12i, 31 bit locking is the default. This will take you to approx 1.8 GB without locking conflicts.

32 bit locking gives access to about 3.6 GB.

Release 4.03 or 4.13 is required to go to 64 bit locking, although this is not possible on Windows 95, 98 and ME.

In versions 4.0 and above, the new OPTION statement is provided to specify the number of bits to be used for locking:

OPTION 33 ( 30 / 31 / 32 / 64 ) (the default is 31): 30 bit support is for compatibility with CIFS (e.g. Samba) when needed. 31 bit locking allows for data files up to about 1.8 gig depending on record size. The larger the record size, the higher the boundary. 32 and 64 bit locking only work on NT/W2K/XP systems. 32 bits support files up to approx 3.6 gig. 32 and 64 bit support is currently only available in releases 4.03 and 4.13.+

Other Notes

• Large file support on Unix/Linux is currently being researched.
• BR will not start two sessions using different lock bit requirements, and a message box is produced when that is attempted.
• The record locking mechanism was substantially revised to enable record locking

without actually locking records. This allows report writers and ODBC to access locked records without interference.