Linux判断大小尾数（big-endian,little-endian）的方法
static union
{
char c[4];
unsigned char l;
} endian_test={ {'l','?','?','b'} }
#define ENDIANNESS ( (char)endian_test.l )

if (ENDIANNESS == 'l')
//little endian
else
//big endian



http://www.cnblogs.com/leezhm/archive/2011/07/19/2110864.html