blksize.c

#include <errno.h>
#include <sys/stat.h>
#include <stdio.h>
#include <string.h>

void print_usage(void)
{
	printf("Usage: blksize DIRECTORY\n");
	printf("Attempts to determine the optimal block size using stat\n");
}

int main(int argc, char *argv[])
{
	if (argc != 2)
	{
		print_usage();
		return 1;
	}

	struct stat stats;
	int rc = stat(argv[1], &stats);

	if (rc != 0)
	{
		printf("Error: %s\n\n", strerror(errno));
		print_usage();
		return rc;
	}

	printf("%ld\n", stats.st_blksize);
	return 0;
}