How do I get the actual directory size, using UNIX/Linux standard tools?
Alternative question: How do I get du to show me the actual directory size (not disk usage)?
Since people seem to have different definitions of the term "size": My definition of "directory size" is the sum of all regular files within that directory.
I do NOT care about the size of the directory inode or whatever (blocks * block size) the files take up on the respective file system. A directory with 3 files, 1 byte each, has a directory size of 3 bytes (by my definition).
Calculating the directory size using du seems to be unreliable.
mkdir foo && du -b foo reports "4096 foo", 4096 bytes instead of 0 bytes. With very large directories, the directory size reported by
du -hs can be off by 100 GB (!) and more (compressed file system).
So what (tool/option) has to be used to get the actual directory size?