[TUHS] V6 networking & alarm syscall

[Larry McVoy]

On Fri, Jan 11, 2019 at 04:08:25PM -0600, reed at reedmedia.net wrote:
> Can someone tell me about SCCS behaviour when renaming/moving or 
> deleting files? In particular, I think the select() code prior to 
> 82/07/15 had different source filenames that no longer exist and the 
> SCCS history was lost.  Anyone else have ideas about this?  I have 
> noticed this with other SCCS spelunking where code was removed and then 
> corresponding "s" files were missing -- but maybe that is just the way 
> the systems that our current snapshots (McKusick discs) of this history 
> were made from. Maybe sccs didn't checkout the history of deleted files 
> by default (that is my guess).

Ah, SCCS is my jam (I rewrote it from scratch as part of BitKeeper).

SCCS didn't know about renames, it was strictly checkin/checkout.
BitKeeper added the concept of "inode" to SCCS though it was not
an integer like an inode in Unix, it was what we called a "key"
and it looked like 

	user at host|pathname|time_t|SCCS_chksum|64bits_of_dev_random

There was a key for each delta and the name of the file was an 
attribute of the delta just as the contents were.  So internally
we worked in keys but externally you used file names and it was
trivial to see where the file had lived.

Anyhoo, I digress, that's all BitKeeper, not SCCS.  If you have
the SCCS history somewhere where I can get it I might be able to
find the file you want.  Just point me at (I know I have that 
set somewhere but no idea where they are).
-- 
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Larry McVoy            	     lm at mcvoy.com             http://www.mcvoy.com/lm