best (most efficient, cross OS, generic) way of locking a file
There is no generic solution!! It will be OS and file system dependent. The best you could do is write (or find) a module that accounts for all of these variances. Though, as JavaFan indicated, even that could be challenge since on some systems you will have to isolate the file.

Elda Taluta; Sarks Sark; Ark Arks

In reply to Re^2: Read/Update File by Argel
in thread Read/Update File by rpike

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