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Constituent: test_endianness     Tag: linux-gcc


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U Union Reference

A union used to reference an integer both as a 32 bit integer and as an array of 4 bytes. More...


Data Fields

unsigned int ui
unsigned char uc [4]


Detailed Description

A union used to reference an integer both as a 32 bit integer and as an array of 4 bytes.

By referencing the same integer as both a 32-bit integer and an array of 4 bytes, one can experimentally determine the endianness of the machine at run time.

If the machine is a little endian machine, element 0 of the array of 4 bytes will match the byte with the least significant portion of the integer, element 1 will match the next least significant portion and so forth.

If the machine is a big endian machine, element 3 of the array of 4 bytes will match the byte with the least significant portion of the integer, element 2 will match the next least significant portion and so forth.


Field Documentation

unsigned char U::uc[4]
 

Reference the value as an array of 4 bytes

unsigned int U::ui
 

Reference the value as a 32-bit integer


The documentation for this union was generated from the following file:
Generated on Sun Dec 12 07:07:53 2004 by doxygen 1.3.3