Thanks to those who commmented.
Clearly I could implement a scheme for pre-munging a netlist into some
binary data structure (tree, or whatever) and using that. That would
require some new auxiliary program to read a text file and create the
new structure, to save Exim having to do it every time. I should have
made it clear in my original comment that what I thought was not
possible was somehow managing to use the existing single-key
"one-database lookup" model in Exim to handle this.
I'll wait until the "read file" code gets released and tried out before
coming back to this.
Philip
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Philip Hazel University Computing Service,
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