#include <sys/mman.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <stdio.h>
#include <stdint.h>
#include <unistd.h>

void
do_work(char *p, size_t size)
{
	printf("parsing %p + %zu\n", p, size);
}

int
main(int argc, char *argv[])
{
	char *filename = argv[1];
	struct stat sb;
	void *p;
	int fd;

	if (argc < 2)
		errx(1, "argument");

	fd = open(filename, O_RDONLY);
	if (fd == -1)
		err(1, "open %s", filename);

	if (fstat(fd, &sb) == -1)
		err(1, "fstat %s", filename);

	p = mmap(NULL, sb.st_size, PROT_READ, MAP_SHARED, fd, 0);
	if (p == MAP_FAILED)
		err(1, "mmap %zu", sb.st_size);

	do_work(p, sb.st_size);

	munmap(p, sb.st_size);

	close(fd);
	return (0);
}