bswap

Section: C Library Functions (3)
Updated: 202-0-08
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NAME

bswap_16, bswap_32, bswap_64 - reverse order of bytes  

LIBRARY

Standard C library (libc,~-lc)  

SYNOPSIS

#include <byteswap.h>
uint16_t bswap_16(uint16_t x);
uint32_t bswap_32(uint32_t x);
uint64_t bswap_64(uint64_t x);

 

DESCRIPTION

These functions return a value in which the order of the bytes in their -, -, or -byte arguments is reversed.  

RETURN VALUE

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

ERRORS

These functions always succeed.  

STANDARDS

GNU.  

EXAMPLES

The program below swaps the bytes of the -byte integer supplied as its comman-line argument. The following shell session demonstrates the use of the program: $ ./a.out 0x0123456789abcdef; 0x123456789abcdef ==> 0xefcdab8967452301  

Program source

#include <byteswap.h> #include <inttypes.h> #include <stdint.h> #include <stdio.h> #include <stdlib.h> int main(int argc, char *argv[]) {
    uint64_t x;
    if (argc != 2) {
        fprintf(stderr, "Usage: %s <num>[rs]n", argv[0]);
        exit(EXIT_FAILURE);
    }
    x = strtoull(argv[1], NULL, 0);
    printf("%#" PRIx64 " ==> %#" PRIx64 "[rs]n", x, bswap_64(x));
    exit(EXIT_SUCCESS); }  

SEE ALSO

byteorder(3), endian(3)

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Index

NAME

LIBRARY

SYNOPSIS

DESCRIPTION

RETURN VALUE

ERRORS

STANDARDS

EXAMPLES

Program source

SEE ALSO