swap_lw_bytes(9r) [osf1 man page]

swap_lw_bytes(9r)														 swap_lw_bytes(9r)

NAME

       swap_lw_bytes, swap_word_bytes, swap_words - General: Perform byte-swapping operations

SYNOPSIS

       unsigned int swap_lw_bytes(
	       unsigned int buffer ); unsigned int swap_word_bytes(
	       unsigned int buffer ); unsigned int swap_words(
	       unsigned int buffer );

ARGUMENTS

       Specifies a 32-bit (4 bytes) quantity.

DESCRIPTION

       The  swap_lw_bytes  interface  performs a longword byte swap. The swap_word_bytes interface performs a short word byte swap. The swap_words
       interface performs a word byte swap. Many computer vendors support devices that use a big endian model of byte  ordering.  Because  Digital
       devices	support the little endian model of byte ordering, there is a need for these byte-swapping interfaces. In addition, some buses (for
       example, the VMEbus) can have specific or implied byte ordering that may require the use of these interfaces.

       Given that a longword is equal to 4 bytes; a short word is equal to 2 bytes; and 1 byte is equal to 8 bits, these interfaces swap bytes	as
       follows: The swap_lw_bytes interface takes the 32-bit quantity specified by the buffer argument and swaps all 4 bytes.  The swap_word_bytes
       interface takes the 32-bit quantity specified by the buffer argument and swaps the individual bytes that make up each word  of  the  32-bit
       quantity.  The swap_words interface takes the 32-bit quantity specified by the buffer argument and swaps the two 16-bit words.

       The following illustration compares the byte swapping performed by these interfaces.

			 31		  0
			  +---+---+---+---+ Starting value:    | a | b | c | d |
			  +---+---+---+---+

			  Long word byte swap
			  (swap_lw_bytes)

			 31		  0
			  +---+---+---+---+ Ending value:      | d | c | b | a |
			  +-------+---+---+

			  Short word byte swap
			  (swap_word_bytes)

			 31		  0
			  +---+---+---+---+ Ending value:      | b | a | d | c |
			  +---+---+---+---+

			 31		  0
			  +---+---+---+---+ Starting value:    |   ab  |   cd  |
			  +---+---+---+---+

			  Word byte swap
			  (swap_words)

			 31		  0
			  +---+---+---+---+ Ending value:      |  cd   |  ab   |
			  +---+---+---+---+

RETURN VALUES

       Upon successful completion, these interfaces return the swapped bytes.

																 swap_lw_bytes(9r)

Check Out this Related Man Page

TIFFswab(3tiff) 														   TIFFswab(3tiff)

NAME

       TIFFswab, TIFFGetBitRevTable, TIFFReverseBits, TIFFSwabShort, TIFFSwabLong, TIFFSwabArrayOfShort, TIFFSwabArrayOfLong - byte- and bit-swap-
       ping routines

SYNOPSIS

       #include <tiffio.h>
       const unsigned char* TIFFGetBitRevTable(int reversed);
       void TIFFReverseBits(u_char* data, unsigned long nbytes)
       void TIFFSwabShort(uint16* data)
       void TIFFSwabLong(uint32* data)
       void TIFFSwabArrayOfShort(uint16* data, unsigned long nshorts)
       void TIFFSwabArrayOfLong(uint32* data, unsigned long nlongs)

       The following routines are used by the library to swap 16- and 32-bit data and to reverse the order of bits in bytes.

       TIFFSwabShort and TIFFSwabLong swap the bytes in a single 16-bit and 32-bit item, respectively.

       TIFFSwabArrayOfShort and TIFFSwabArrayOfLong swap the bytes in an array of 16-bit and 32-bit items, respectively.

       TIFFReverseBits replaces each byte in data with the equivalent bit-reversed value. This operation is done  with	a  lookup  table,  TIFFBi-
       tRevTable,  which is declared public. A second table, TIFFNoBitRevTable, is also declared public, and is a lookup table that can be used as
       an identity function. That is, TIFFNoBitRevTable[n] == n.

       See attributes(5) for descriptions of the following attributes:

       +-----------------------------+-----------------------------+
       |      ATTRIBUTE TYPE	     |	    ATTRIBUTE VALUE	   |
       +-----------------------------+-----------------------------+
       |Availability		     |SUNWTiff			   |
       +-----------------------------+-----------------------------+
       |Interface stability	     |Uncommitted		   |
       +-----------------------------+-----------------------------+

       libtiff(3)

       This man page was originally written by Sam Leffler. Updated by Breda McColgan, Sun Microsystems Inc., 2004.

								    05 Apr 2004 						   TIFFswab(3tiff)

Linux and UNIX Man Pages

swap_lw_bytes(9r) [osf1 man page]

Check Out this Related Man Page