🚀 go-pugleaf

In article <13342@cbmvax.commodore.com> jesup@cbmvax (Randell Jesup) writes:
>
> In article <3fco02lsb9LE01@amdahl.uts.amdahl.com> ked01@juts.ccc.amdahl.com (Kim DeVaughn) writes:
>
> >Are you saying this is now the documented behavior for the fib_NumBlocks
> >entry (for the FFS), or is it still better to compute them yourself from
> >fib_Size, so as not to break in future releases?
> 
> 	Computing it yourself is never really safe.  It depends on how the
> FS works internally.  Take what it gives you, with the understanding that
> this really is only an internal measure of storage to the filesystem.  On some
> filesystems I can imagine (easily), the number of blocks a file takes may
> depend on fragmentation.  Certainly the number of blocks can and will
> vary from filesystem to filesystem for a given file.
> 
> 	I advise against writing code that uses blocks for anything more than
> user informational display or hints.

So the bottom line is that there is no supported* way to determine the block
count of a file.  And hence, there is no supported method of determining if
a file on one device will "fit" on another device without actually attempting
the copy operation.

Unfortunate.

/kim

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