JdBP>> I think that Leonard is trying to make the point that using 
 JdBP>> FCBs for "fast deletions" is pointless in those 
 JdBP>> environments, because it *isn't* actually faster that doing 
 JdBP>> things the more up-to-date way using a simple 
 JdBP>> findfirst/findnext loop.

 LA> I *have* compared it Johnathan, and it's a whole big pile faster    
 LA> than running a loop, which, of course, is the backup routine in    
 LA> case the drive in question is HPFS (since warp intentionally    
 LA> traps if you try this on HPFS with a wildcard spec).

It's only faster on DOS, though.  It *isn't* faster on non-DOS operating
systems, such as OS/2 or Windows NT.  Try measuring it on something other than 
DOS.

This was demonstrated a year or so ago in this very echo, with people using
the 4DOS DEL command with and without the /Q switch (which selects between
using FCBs and using MS-DOS version 2.0 style deletion) and discovering that
the two operate at exactly the same speed.  Unfortunately, I don't remember
who it was who sat down and tested it.

 LA> Think about it...which is faster, looping 500 times to do a 
 LA> findnext/handle delete, or once to nuke the entire directory 
 LA> contents?

It's important to remember, however, that FCB wildcard deletion does *exactly
that* under the covers on operating systems such as OS/2 and Windows NT.  An
OS/2 VDM, for example, implements CP/M style wildcard deletion by internally
running a DosFindFirst/DosFindNext/DosFindClose loop.  This is the reason why
CP/M style file deletion *isn't* faster on non-DOS platforms.  It's doing
exactly the same thing as an application would be doing if it performed the
DosFind{First,Next,Close} loop itself.

The idea that "FCBs are faster" is only true when one uses DOS for one's
operating system.  But operating systems that are *not* based upon DOS but on
which one can run DOS programs, such as OS/2 and Windows NT, have been in
widespread use for 5 to 8 years now.  The generality that "FCBs are faster" is 
no longer true, and hasn't been for many years.  Even on DOS-Windows 3.1 or
DOS-Windows 95/98 with "32-bit file access" enabled it isn't true.  It wasn't
even true on DOS in the 1980s on machines attached to LANs.

So this "little trick" will go away because it is no longer useful to DOS
programmers, which is in turn because the premise that it is based upon is not 
true for the large majority of systems where DOS programs are run these days.

 ¯ JdeBP ®

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