Date   : Sat, 06 Oct 1984 05:34:00 MDT (Sat)
From   : Keith Petersen <W8SDZ@Simtel20.ARPA>
Subject: Resident System Extension (RSX) for CP/M 2.2

Now you can add RSX's to CP/M 2.2.  The following files are now
available from SIMTEL20:

Filename                       Type     Bytes   CRC

Directory MICRO:<CPM.22RSX>
22RSX.ASM.1                    ASCII    13295  520BH
22RSX.DOC.1                    ASCII    10994  3572H
CONSOLE.22X.1                  ASCII     5539  DADBH
CONSTAT.ASM.1                  ASCII     1473  30E7H
EXPTABS.22X.1                  ASCII     1856  0931H
REMOVE.COM.1                   COM        896  7887H
REMOVE.HEX.1                   ASCII     2195  5B04H

...and for those who want the entire package and can FTP ITS-binary
files:
22RSX.LBR.1                    COM      23296  A4F8H

Here's a brief excerpt from the author's .DOC file:

     22RSX: a Resident System Extension facility for CP/M 2.x

22RSX  is  a  facility to allow the installation and  removal  of
Resident System Extensions.  Briefly, an extension is an addition
to BDOS that can monitor,  trap,  alter or process any BDOS  call 
made  from an applications program.  This came about after I  had 
worked  a bit with CP/M 3.0.  It's RSX facility impressed me with 
the fact that it made it relatively easy to 'patch' the operating 
system  to add things such as remote  consoles,  print  spoolers, 
etc.  Since I had some experience with CP/M, I decided to write a 
similar system for CP/M 2.2.
Note:  I  realize  that  there is an RSX manager written  by  Jim 
Lopushinsky for CP/M 2.2.  I have never used it,  but from what I 
have  seen and read,  it seems to require a fair amount  of  work 
with DDT, M80, etc. This system, on the other hand, takes care of 
all installation. All you have to do is write a module, insert it 
in the driver,  assemble, load and run! And your finished product 
will,  assuming  that it uses standard CP/M calls and procedures, 
run on any other CP/M system without modification.

This system, as distributed, consists of the following files:

   22RSX.ASM    -------> The module installation driver.
   REMOVE.OBJ   -------> The module removal program.
   22RSX.DOC    -------> Documentation.
   EXPTABS.22X  -------> A demonstration module.
   CONSOLE.22X  -------> Another demonstration module.
   CONSTAT.ASM  -------> The companion access program for CONSOLE.22X.

--Keith