Tyler asked:
> I assume that could be done to get the equiv of the
> microsoft lobyte, loword, hiword, hibyte and etc?
> If that's to combine them, how would you get them apart?
I should have stressed that the conversion from integer to
chars is implementation-independent. C guarantees a char to
be a single byte (not necessarily of 8 bits!) and that
integers are represented in such a way that bitwise
operations on them make sense. (Otherwise there'd be little
point in having bitwise operators.)
I don't know what Microsoft's own types are but they're
probably #define'd in a header file somewhere in terms of
C's basic types. The Gnu C library does this for its own
types like uint32_t (guaranteed to be 32 bits no matter what
machine is used).
To go the other way (char[] to integer) can be done using
shift and add operations:
#include <stdio.h>
#include <limits.h>
int main(void)
{
unsigned long long i = 1234567890;
unsigned long long j;
unsigned char c[4];
printf("Your integers are %i bits\n", CHAR_BIT *
sizeof(i));
/* Integer to char[]: */
c[0] = i & 0xff; /* least significant byte */
c[1] = (i & 0xff00) >> 8;
c[2] = (i & 0xff0000) >> 16;
c[3] = (i & 0xff000000) >> 24;
printf("0x%08x == ", i);
printf("0x%02x%02x%02x%02x", c[3], c[2], c[1], c[0]);
/* char[] to integer: */
j = c[0] + (c[1] << 8) + (c[2] << 16) + (c[3] << 24);
printf(" == 0x%08x\n", j);
return 0;
}
You need to ensure that your integer type is big enough to
hold the result without overflowing!
David
