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#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <errno.h>
#include <string.h>
#include <libjio.h>

#define FILENAME "test1"
#define TEXT "Hello world!\n"

int main(void)
{
	int r;
	jfs_t *file;
	struct jtrans *trans;
	struct jfsck_result result;

	/* check the file is OK */
	jfsck(FILENAME, NULL, &result, 0);

	/* and open it */
	file = jopen(FILENAME, O_RDWR | O_CREAT | O_TRUNC, 0600, 0);
	if (file == NULL) {
		perror("jopen");
		return 1;
	}

	/* write two "Hello world"s next to each other */
	trans = jtrans_new(file, 0);
	jtrans_add_w(trans, TEXT, strlen(TEXT), 0);
	jtrans_add_w(trans, TEXT, strlen(TEXT), strlen(TEXT));
	r = jtrans_commit(trans);
	if (r < 0) {
		perror("jtrans_commit");
		return 1;
	}

	/* at this point the file has "Hello world!\nHello world!\n" */

	/* now we rollback */
	r = jtrans_rollback(trans);
	if (r < 0) {
		perror("jtrans_rollback");
		return 1;
	}

	/* and now the file is empty! */

	jtrans_free(trans);
	jclose(file);
	return 0;
}