FA> I'm in the process of making up a library, that may have more than one 
FA> copies running at any time. If i do it in C i'll have to have a number of 
FA> instances of the struct and pass it to the functions.
FA> If i find that it slows execution too much i may have to opt for C++ and 
FA> classes, 

Show me the C++ code you think would be slower if written in C. Or better
still, write both the C and C++ versions, and have a look at the assembler
generated for each, and look at the relative code.  They should be the same
(speedwise).  BFN.  Paul. 
@EOT:

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