Handy four char code decoder

In a similar vein, here's an inline function that will convert the SPErr (or AIErr) into it's four-character human-readable code:

] inline void ConvertSPErr(const SPErr error, char* buffer)
] {
] static const int kErrorByteSize = sizeof(SPErr);
] static const int kCharBitCount = sizeof(char) * 8;
] static const int kBaseMask = 0xff;
] int mask = 0;
]
] for (int i = 0; i < kErrorByteSize; i++) {
] mask = kBaseMask << (kCharBitCount * i);
] int value = error & mask;
] value = value >> (kCharBitCount * i);
] buffer[kErrorByteSize - i - 1] = (char)value;
] }
]
] buffer[kErrorByteSize] = 0;
] }