Shinjji
asked on
Byte swapping a double in C / C++
Hi, im converting a program from a silicon graphics machine to the PC.
I would like to know how to byte swap a double
I have tried the following but it doesnt seem to work :-
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void byteSwapDouble(double *ptrValue)
{
double *ptrTemp;
char * swapA, swapB;
ptrTemp = ptrValue;
swapA = (char *)ptrTemp;
swapB = swapA[0];
swapA[0] = swapA[7];
swapA[7] = swapB;
swapB = swapA[1];
swapA[1] = swapA[6];
swapA[6] = swapB;
swapB = swapA[2];
swapA[2] = swapA[5];
swapA[5] =swapB;
swapB = swapA[3];
swapA[3] = swapA[4];
swapA[4] = swapB;
ptrTemp = (double *)swapA;
ptrValue = ptrTemp;
}
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I would like to know how to byte swap a double
I have tried the following but it doesnt seem to work :-
--------------------------
void byteSwapDouble(double *ptrValue)
{
double *ptrTemp;
char * swapA, swapB;
ptrTemp = ptrValue;
swapA = (char *)ptrTemp;
swapB = swapA[0];
swapA[0] = swapA[7];
swapA[7] = swapB;
swapB = swapA[1];
swapA[1] = swapA[6];
swapA[6] = swapB;
swapB = swapA[2];
swapA[2] = swapA[5];
swapA[5] =swapB;
swapB = swapA[3];
swapA[3] = swapA[4];
swapA[4] = swapB;
ptrTemp = (double *)swapA;
ptrValue = ptrTemp;
}
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ASKER CERTIFIED SOLUTION
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ASKER
Good stuff.
void byteSwapDouble(double *ptrValue)
{
char temp;
swapByte(ptrValue, ptrValue+7, temp);
swapByte(ptrValue+1, ptrValue+6, temp);
swapByte(ptrValue+2, ptrValue+5, temp);
swapByte(ptrValue+3, ptrValue+4, temp);
}