Union struct and bitfield in C
please see updated version: union struct bitfield and endianess in C
Typical usage of a bitfield with struct and union in C
/*
* Copyright © 2016 Enrico Rossi <e.rossi@tecnobrain.com>
*
* This work is free. You can redistribute it and/or modify it under the
* terms of the Do What The Fuck You Want To Public License, Version 2,
* as published by Sam Hocevar. See http://www.wtfpl.net/ for more details.
*/
#include <stdlib.h>
#include <stdint.h>
#include <stdio.h>
union status_t {
struct {
uint8_t b7:1;
uint8_t b6:1;
uint8_t b5:1;
uint8_t b4:1;
uint8_t b3:1;
uint8_t b2:1;
uint8_t b1:1;
uint8_t b0:1;
} bits;
uint8_t byte;
};
int main(void)
{
union status_t status;
int i;
printf("The size of the union is: %01x byte.\n", sizeof(status));
for (i=0; i<8; i++) {
status.byte = (1<<i);
printf("Setting bit %d: %01x%01x%01x%01x%01x%01x%01x%01x\n", i,
status.bits.b0, status.bits.b1, status.bits.b2, status.bits.b3,
status.bits.b4, status.bits.b5, status.bits.b6, status.bits.b7);
}
return(0);
}