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Data Types

A long double is 16 bytes on both architectures, but only 80 bits are significant in long double data types on Intel-based Macintosh computers.

A bool data type is a single byte on an x86 system, but four bytes on a PowerPC architecture. This size difference can cause alignment problems. You should use fixed-size data types to avoid alignment problems. (The bool data type is not the Carbon Boolean type, which is a fixed size of 1 byte.)

Existing document formats that include the bool data type as part of a data structure that is written directly to disk can be problematic because the data structure might not be laid out the same on both architectures. If you update the data structure definition to use the UInt32 data type or another fixed-size four-byte data type, the structure should then be portable, although you must swap bytes appropriately.

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