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TIFF and LibTiff Mail List Archive

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1994.09.16 04:17 "TIFF Bit Ordering Versus Fill Order", by John M Davison
1994.09.16 17:42 "Re: TIFF Bit Ordering Versus Fill Order", by Sam Leffler
1994.09.19 06:55 "Re: TIFF Bit Ordering Versus Fill Order", by Karsten Spang
1994.09.19 15:26 "Re: TIFF Bit Ordering Versus Fill Order", by Sam Leffler
1994.09.19 11:48 "Re: TIFF Bit Ordering Versus Fill Order", by Niles Ritter
1994.09.19 22:48 "Re: TIFF Bit Ordering Versus Fill Order", by Sam Leffler
1994.09.20 00:03 "Re: TIFF Bit Ordering Versus Fill Order", by Joe Moss
1994.09.20 07:00 "Re: TIFF Bit Ordering Versus Fill Order", by Fredrik Lundh
1994.09.19 17:34 "Now that you mention bit order...", by Craig Jackson
1994.09.19 19:04 "Bit order revisited ...", by Scott Wagner
1994.09.19 22:46 "Re: Now that you mention bit order...", by Sam Leffler
1994.09.19 23:53 "RE: Now that you mention bit order...", by Craig Jackson
1994.09.20 13:25 "RE: Now that you mention bit order...", by Scott Wagner
1994.09.22 22:50 "Re: Now that you mention bit order...", by John M Davison
1994.09.22 23:49 "Re: Now that you mention bit order...", by Sam Leffler
1994.09.19 23:31 "Re: TIFF Bit Ordering Versus Fill Order", by Jim Arnold
1994.09.20 12:29 "MSB vs. LSB. (Was: TIFF Bit Ordering Versus Fill Order)", by Thomas Kinsman

1994.09.20 07:00 "Re: TIFF Bit Ordering Versus Fill Order", by Fredrik Lundh

However, a possible way to define host bit order would be to use the C bit-field struct operations.

Is this a compiler-implementation dependent approach?

ANSI C, Section 3.5.2.1:

    "The order of allocation of bit-fields within a unit
    (high-order to low-order or low-order to high-order) is
    implementation-defined."

The spec also states that it "need not be possible to express the address of each individual bit of an object", and that shifting n bits to the left is the same as multiplying by 2 raised to the power n.

To sum that up, there is no such thing as a "host bit order" when hacking C (at least not with the same meaning as "host byte order").

For additional reading on bit and byte orders, see IEN 137.

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