#include <errno.h>    /* for errno */
#include <error.h>    /* for error(3gnu) */
#include <fcntl.h>    /* for O_RDONLY */
#include <inttypes.h> /* for PRI*, uint*_t, int*_t */
#include <stdbool.h>  /* for bool */
#include <stdio.h>    /* for printf */
#include <sys/stat.h> /* for open(2), fstat(2) and struct stat */
#include <unistd.h>   /* for close(2), read(2), lseek(2), SEEK_SET */

int main(int argc, char *argv[]) {
	bool err = false;
	for (int i = 1; i < argc; i++) {
		const char *filename = argv[i];

		int fd = open(filename, O_RDONLY);
		if (fd < 0) {
			err = true;
			error(0, errno, "open %s", filename);
			continue;
		}

		struct stat st;
		if (fstat(fd, &st) < 0) {
			err = true;
			error(0, errno, "fstat %s", filename);
			close(fd);
			continue;
		}

		if (lseek(fd, st.st_size/2, SEEK_SET) < 0) {
			err = true;
			error(0, errno, "lseek %s", filename);
			close(fd);
			continue;
		}

		uint8_t b;
		int n = read(fd, &b, sizeof(b));
		if (n <= 0) {
			if (n == 0)
				error(0, 0, "read %s: unexpected end of file", filename);
			else
				error(0, errno, "read %s", filename);
			err = true;
			close(fd);
			continue;
		}

		printf("%"PRId64":%"PRIx8"  %s\n", (int64_t)st.st_size, b, filename);
		close(fd);
	}
	return err ? 1 : 0;
}