Zephyr Native POSIX Flash driver read and write sample

zephyr_flash_rw_sample.c

#include <zephyr.h>
#include <sys/printk.h>
#include <device.h>
#include <drivers/flash.h>

// How to build.
// cd ~/zephyrproject
// mkdir app
// cd app
// cp -r ../../zephyr/samples/hello_world/ .
// cd hello_world
// west build -b native_posix_64
// west build -t menuconfig
//  Enable Device Drivers -> Flash hardware support -> Native POSIX Flash driver
//  Save configuration and Quit.
//  Edit src/main.c
// west build -t run
//  A file named "build/flash.bin" will generate after run. 
// cat build/flash.bin #=> Z

void main(void)
{
	struct device *flash;
	off_t offset = 0;
	uint8_t data;
	int ret;

	printk("Hello World! %s\n", CONFIG_BOARD);

	flash = device_get_binding(DT_FLASH_DEV_NAME);
	if (flash == NULL) {
		printk("device not found.  Aborting.\n");
		return;
	}

	ret = flash_read(flash, offset, &data, 1);
	if(ret) {
		printk("error %d\n", ret);
		return;
	}

	printk("read data is : %d(%c)\n", data, data);

	data = 'Z';
	ret = flash_write(flash, offset, &data, 1);
	if(ret) {
		printk("error %d\n", ret);
		return;
	}

	printk("write data is : %d(%c)\n", data, data);
}