Re: question about memcpy()

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"Ed Weir (ComCast)" <Anon@xxxxxxxx> wrote in message
news:bsydnTz9w9b0MdPZRVn-vQ@xxxxxxxxxxxxxx

"kathy" <yqin_99@xxxxxxxxx> wrote in message
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| Yes. You are right. No setting of /Zp in one project and another one
| has pack() setting.
|
| Could you explain why the first member of MAC_ADDR as a 6 byte array is
| problematic?
|

If default packing is 8, there will be two bytes slack...

I always use /Zp1.

- Ed.


I don't see that it's necessary to "always" use /Zp1. There are many
computations that are faster/more efficient if the default packing is used,
such that it's usually not necessry (or advisable) to compile the entire
project at /Zp1

You can force packings for particular structures that need them using the
"pack" #pragma:

#pragma (pack, temp_byte_packing, 1)

// your structures here

#pragma (pop, temp_byte_packing)

See http://msdn2.microsoft.com/en-us/library/2e70t5y1(VS.80).aspx

Mike


.

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