File offset for locking



USupported on UNIX


The DBLHIGHPOS environment variable specifies the maximum file offset for locking.


Either the maximum file offset or WARN, to warn when the lock attempt is rejected.


DBLHIGHPOS sets the maximum file offset for locking when system option #33 is not set (conventional locking). By convention, Synergy ISAM files use the highest addressable file offset to lock during OPEN processing for enforcement of exclusive file locking. This value is normally set to 0x7FFFFFFF on 32‑bit machines.

At runtime, a lock attempt is made at the default position. If the lock attempt is rejected at that position, it adjusts down until it succeeds. To be warned of this, set DBLHIGHPOS to “WARN.” If you get a fatal “Record locking problem” error, you can either set system option #33 or use DBLHIGHPOS. We recommend using DBLHIGHPOS so that exclusive file sharing is not disabled.


This environment variable should be set only in extreme circumstances; all users accessing the same data files must also have the same setting, including Synergy/DE xfServer.

Setting location

The environment.

Used by

Runtime, fcompare, fconvert, isutl