Date   : Thu, 02 Aug 1990 09:00:26 edt
From   : <DAN@BSN.MCEO.DG.COM>
Subject: ZCPR 3.3 FAST ERA/REN/PROT algorithm

CEO summary:
I just recently moved from my own (very system dependent) command 
processor replacement to ZCPR 3.3.  One thing that I noticed is that 
commands such as ERA, REN, PROT and any other program that work to 
modify the directory can be made to work a lot faster than they 
already are.  From what I can tell, ERA will first scan the directory 
using the search and next functions, and the delete each file 
individually with the delete command.  This requires that the 
directory be scaned once no matter what, and once for each file to be 
deleted.  The faster way for the simple ERA would to be scan the 
directory using the search and next functions, but when I directory 
entry is found, print it, change the user to E5 and then to a BIOS 
write.  BIOS is already set to the correct DMA, track, and sector 
because of the read to get that sector there in the first place.  
This way the directory is read once (very fast).  For more complex 
operations such as querying for verification, read the directory 
once, perform the queries, and then scan a second time, changing only 
the files that the user has allowed to be changed.  Has anybody 
thought to do this?  How about getting it changed (I might be able to 
do it myself, but I need info on getting this tested and distributed)?
Thanks. dan_zehme@bsn.ceo.dg.com