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bswap(3) [linux man page]

BSWAP(3)						     Linux Programmer's Manual							  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> ", argv[0]); exit(EXIT_FAILURE); } x = strtoul(argv[1], NULL, 0); printf("0x%" PRIx64 " ==> 0x%" PRIx64 " ", x, bswap_64(x)); exit(EXIT_SUCCESS); } SEE ALSO
byteorder(3), endian(3) Linux 2019-03-06 BSWAP(3)

Check Out this Related Man Page

BSWAP(3)						     Linux Programmer's Manual							  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> ", argv[0]); exit(EXIT_FAILURE); } x = strtoul(argv[1], NULL, 0); printf("0x%" PRIx64 " ==> 0x%" PRIx64 " ", x, bswap_64(x)); exit(EXIT_SUCCESS); } SEE ALSO
byteorder(3), endian(3) COLOPHON
This page is part of release 4.15 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/. Linux 2017-09-15 BSWAP(3)

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