Date   : Fri, 25 Feb 1983 00:58:56 EST (Fri)
From   : Rick Conn <rconn@brl.arpa>
Subject: Re: HOW TO..

        The library I just released to SIG/M  (SYSLIB  2.4)  con-
tains  many  assembly  language  routines  for doing the kinds of
things you are interested in.  To be exact, there  are  130  rou-
tines  in  the  library which deal with the disk, math functions,
sorting, ZCPR2, and other topics.  Source code is  available  for
everything if you want to study it.

        In answer to your  first  question  (about  finding  free
space  on  a  disk), yes.  The SDIR.MAC module of SYSLIB 2.4 con-
tains a routine called DFREE which returns  the  number  of  free
bytes  (in  K) on a disk.  You just call DFREE after logging into
the desired disk, and it returns this value in  the  DE  register
pair.  The source code for this routine is under 2 pages in size,
and it works for any CP/M 2.2 system.

        Re your second question (accessing directory  info),  the
SDIR.MAC  module  also  has  routines  to do this.  DIRLOAD loads
basic file info on all files on your disk into a  memory  buffer,
and DIRSLOAD does the same as DIRLOAD but includes necessary info
to compute file sizes and  runs  slightly  slower  as  a  result.
These  are  far  more complex than DFREE, and they are documented
(along with all the SYSLIB 2.4 routines) in the SYSLIB.HLP  files
on  MC  and  the SYSLIB documents.  Workman should have a copy of
the SYSLIB documents and the ZCPR2 documents by now, and you  can
get the interface info from him.

                Rick