Large objects

I am having trouble with writing to large objects.
 I am not using lseek, as I have heard it is broken. I simply
read the whole thing into a buffer, edit it, and (attempt to)
write it back out. 
 I am doing this from TCL.
 Has any one used large objects successfully?

-- 
Kurt Seel, Systems Engineer
Unified Technologies Corp.
Phone : 610 964 8200
Email : kseel@ut{anti-spam]corp.com

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