INIT disk/DIRECTORIES=n

[Jack Trachtman]

I'm back to trying to understand this INIT option, which I've never understood.

This is clear:  INIT disk/HEADERS=n directly effects the size of the INDEXF.SYS file, which I've just reconfirmed in some quick tests (I understand what HEADERS are so this was just a sanity check).

But, I've never understood what the /DIRECTORIES=n switch does.  The HELP text is unclear, I couldn't find more info with a web search, and in some quick testing, using N=16 (the default) or N=16000 (the max allowed) seems to make no difference in the sizes of the files created by the INIT operation.

Would someone explain what this switch does and how I should consider using it?  TIA

[Hoff · Accepted solution]

Are you conflating the index file INDEXF.SYS and the 000000.DIR Master File Directory (MFD)?

The INITIALIZE /DIRECTORIES qualifier pre-allocates the 000000.DIR master file directory directory file,  and is not particularly useful for most cases.   Not unless you're going to immediately fill 000000.DIR with a gazillion files. 

Related: OpenVMS Tips: Disks and the INITIALIZE Command

[Jack Trachtman]

Ah yes, that simple.  I was expecting something more complicated.  Thank you