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Annotation of coherent/a/usr/man/ALL/byteordering, revision 1.1.1.1

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                      3: byte ordering         Technical information         byte ordering
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                      8: Machine-dependent ordering of bytes
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                     10: 
                     11: Byte ordering  is the order in which a  given machine stores suc-
                     12: cessive bytes of a multibyte data item.  Different machines order
                     13: bytes differently.
                     14: 
                     15: The following example displays  a few simple examples of byte or-
                     16: dering:
                     17: 
                     18: 
                     19: main()
                     20: {
                     21:         union
                     22:         {
                     23:                 char b[4];
                     24:                 int i[2];
                     25:                 long l;
                     26:         } u;
                     27:         u.l = 0x12345678L;
                     28: 
                     29: 
                     30: 
                     31:         printf("%x %x %x %x\n",
                     32:                 u.b[0], u.b[1], u.b[2], u.b[3]);
                     33:         printf("%x %x\n", u.i[0], u.i[1]);
                     34:         printf("%lx\n", u.l);
                     35: }
                     36: 
                     37: 
                     38: When run  on ``big-endian'' machines,  such as the  M68000 or the
                     39: Z8000, the program gives the following results:
                     40: 
                     41: 
                     42:         12 34 56 78
                     43:         1234 5678
                     44:         12345678
                     45: 
                     46: 
                     47: As you  can see, the  order of bytes  and words from  low to high
                     48: memory is the same as is represented on the screen.
                     49: 
                     50: However, when this  program is run on ``little-endian'' machines,
                     51: such as the PDP-11, you see these results:
                     52: 
                     53: 
                     54:         34 12 78 56
                     55:         1234 5678
                     56:         12345678
                     57: 
                     58: 
                     59: As  you can  see, the  PDP-11 inverts the  order of  bytes within
                     60: words in memory.
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                     64: COHERENT Lexicon                                           Page 1
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                     69: byte ordering         Technical information         byte ordering
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                     72: 
                     73: Finally,  when the  program is  run  on the  i8086 you  see these
                     74: results:
                     75: 
                     76: 
                     77:         78 56 34 12
                     78:         5678 1234
                     79:         12345678
                     80: 
                     81: 
                     82: The i8086 inverts both words and long words.
                     83: 
                     84: ***** See Also *****
                     85: 
                     86: C language, canon.h, data formats, technical information
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                    130: COHERENT Lexicon                                           Page 2
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