[COFF] [TUHS] Re: History of cal(1)?

[Bakul Shah via COFF]

On Sep 26, 2025, at 7:26 AM, Dan Cross via COFF <coff at tuhs.org> wrote:
> 
> A random thought: some versions of UFS have support for something they
> call "fast symlinks".  Symbolic links, of course, are just files that
> contain a string naming some other file, and if a pathname has a
> component naming a symlink when walked by `namei`, that string is
> substituted for the name of the symlink.  But often these names are
> very short, and recall that the `inode` contains some space for disk
> block addresses (60 bytes in UFS on 4.1C, but this got bigger in later
> versions).  The idea with fast symlinks is that, if the target file
> name of a symlink is short enough, the system can just store it in the
> space that would normally be used for block addresses; there's no need
> to allocate a separate fragment from a disk block, let alone bear the
> cost of allocating a buffer and fetching a block from disk, if a short
> name can be written directly into the inode.

Storing symlink or small file content in the inode breaks unix
semantics: whether you can hard link to a file would depends
on its size!