Re: macro help

On Sun, 30 Sep 2007 04:14:19 -0700, William Pursell wrote:

On 30 Sep, 10:26, inftoc...@xxxxxxxxx wrote:
I wrote a macro to read 8 bytes from a byte stream. Am not
sure if it is working ok. Can anyone please point out if there looks
to be a problem!

#define READ64(b) ( (uint64_t(*b)) << 56) + ((uint64_t(*(b+1))) << 48)
+ ((uint64_t(*(b+2))) << 40) +((uint64_t(*(b+3))) << 32)+((uint64_t(*(b
+4))) << 24) + (( uint64_t(*(b+5))) << 16) + (( uint64_t(*(b+6))) <<
8) + ( *(b+7))

Here b is a pointer to an unsigned char.

Lots of problems:

The endianness of the machine will have
an impact, certainly.

I think he did that to have the same format on all machines.
Otherwise he could use memcpy().
--
Army1987 (Replace "NOSPAM" with "email")
A hamburger is better than nothing.
Nothing is better than eternal happiness.
Therefore, a hamburger is better than eternal happiness.

.

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