I noticed that a file of 10485760 bytes would be listed as 11MB by du -m.
The -h "humanize" is correct and lists as 10MB.
du.c uses:
(void)printf("%lld\t%s\n",
(long long)howmany(blocks, (int64_t)blocksize),
This works better for me:
printf("%ld\n", (long)((int64_t)blocks / blocksize));
But that doesn't help for files less than a megabyte which will then be
displayed as a zero.
As another example, a file of 3372684 bytes is 3.21644MB. du -m would
round up to 4. While my printf above prints "3".
I am not sure what correct behaviour should be.
Either way, the du man page should document about this as it is
misleading.