bswap_16, bswap_32, bswap_64 - reverse order of bytes


   #include <byteswap.h>



   These  macros  return  a value in which the order of the bytes in their
   2-, 4-, or 8-byte arguments is reversed.


   These macros  return  the  value  of  their  argument  with  the  bytes


   These macros always succeed.


   These macros are GNU extensions.


   The program below swaps the bytes of the 8-byte integer supplied as its
   command-line argument.  The following shell  session  demonstrates  the
   use of the program:

       $ ./a.out 0x0123456789abcdef
       0x123456789abcdef ==> 0xefcdab8967452301

   Program source

   #include <stdio.h>
   #include <stdint.h>
   #include <stdlib.h>
   #include <inttypes.h>
   #include <byteswap.h>

   main(int argc, char *argv[])
       uint64_t x;

       if (argc != 2) {
           fprintf(stderr, "Usage: %s <num>\n", argv[0]);

       x = strtoul(argv[1], NULL, 0);
       printf("0x%" PRIx64 " ==> 0x%" PRIx64 "\n", x, bswap_64(x));



   byteorder(3), endian(3)


   This  page  is  part of release 4.09 of the Linux man-pages project.  A
   description of the project, information about reporting bugs,  and  the
   latest     version     of     this    page,    can    be    found    at


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