bswap(3)

NAME

   bswap_16, bswap_32, bswap_64 - reverse order of bytes

SYNOPSIS

   #include <byteswap.h>

   bswap_16(x);
   bswap_32(x);
   bswap_64(x);

DESCRIPTION

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

RETURN VALUE

   These macros  return  the  value  of  their  argument  with  the  bytes
   reversed.

ERRORS

   These macros always succeed.

CONFORMING TO

   These macros are GNU extensions.

EXAMPLE

   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>

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

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

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

       exit(EXIT_SUCCESS);
   }

SEE ALSO

   byteorder(3), endian(3)

COLOPHON

   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
   https://www.kernel.org/doc/man-pages/.

---

Free and Open Source Software