Introduction to PATCHCPM.
Why you might want to PATCHCPM.
How to use.
How to modify.
Features and limitations.
: Introduction to PATCHCPM.

              This utility enables you  to  easily  PATCHCPM.   It  is
         simply  a collection of available patches put together in one
         program.  It was purposely written in 8080 code and is easily
         modified.

              Feel free to add any other patches you have come  across
         - if you do then how about sharing them with me?

                                  Jim Dreher
                               1937 Armory Road
                                  Barstow, CA
                                     92311

                        Barstow RCP/M -- (619) 256-3914

: Why you might want to PATCHCPM.

              I see a lot of people are switching to ZCPR2, but I have
         decided  NOT  to  go  that  route  on my ROBIN.  Don't get me
         wrong, I agree that ZCPR2 has some really nice features,  but
         the  ROBIN simply doesn't have that much disk space to manage
         (only 169k per disk).  I believe that ZCPR2 is better  suited
         for  a  large disk system such as a 5 or 10Mb Winni (or maybe
         even a double-density 8  inch).   That  way  you  would  have
         enough  room to make the USER areas work to your advantage --
         very similar to the heiarchial structure of UNIX or VMS.

              Consider an alternative system  that  I  currently  use.
         This works GREAT on a system with four drives -- I don't know
         if  it  would  be  all  that  great on a system with only two
         drives.  Everybody and their grandmother has  written  better
         utilities  than  the  CCP  "built-in"  ones, but are a little
         awkward to use.  How many times can you  type  XDIR  or  ERAQ
         without  looking  at the keyboard and not make a mistake?  My
         utility called PATCHCPM solves this problem.  Using  PATCHCPM
         here's what I've done:



         1.   Using  a  patch by Lewis Moseley, my DELETE key now
              works the same as my BACK SPACE key.  (Hooka!)

         2.   Using another patch from an  unknown  hacker,  I've
              designated  my drive A to be my "system drive".  If
              I'm logged into a disk other than A and call for  a
              program   that's   not  on  that  disk,  CP/M  will
              automatically go and get it from drive A.  The next
              patch indicates how useful this is.

         3.   Using patches that I thought up (I  don't  know  if
              I'm  the  first, but I haven't seen them documented
              anywhere else yet), I disabled the "built-in"  DIR,
              ERA,  and  TYPE  commands.   Now when I type in DIR
              instead of doing the directory, CP/M  looks  for  a
              file called DIR.COM.  Then I RENamed the following:
              SD.COM became DIR.COM, ERAQ.COM became ERA.COM, and
              TYPE17.COM  became  (you  guessed  it!)   TYPE.COM.
              Reference #2 above, now I can get a directory  from
              any  disk  in any drive and the DIR.COM only has to
              be on the disk in drive A!

              I use the patch that makes drive A the system drive  and
         I  find  it very useful and more importantly practical to use
         (on a ROBIN with four drives).  On my "system disk"  are  all
         of  the  programs  that  I  frequently use and can be invoked
         while logged into any drive.  The best example is my new  DIR
         command  --  I  ran PATCHCPM to enable drive A as the "system
         drive", disabled the "built-in" DIR command, then I did  "PIP
         A:DIR.COM=B:SD.COM[V]".    Now  I  can  get  a  comprehensive
         directory while logged into any disk and only the system disk
         needs to have the DIR.COM file!  (SD.COM is Super Directory -
         VERY NICE!).

              There are many other worthy replacements  avaliable  for
         the  "built-in"  CCP commands.  I also use TYPE17.COM renamed
         to  TYPE.COM  and  ERAQ.COM  renamed  to  (you  guessed  it!)
         ERA.COM.


              CP/M Copyright,TM Digital Research
              ZCPR2 written by Richard Conn
              ROBIN is Digital Equipment Corporation's VT180.
              SD.COM written by David Boruff.
              Unix TM Bell Labs
              VMS TM Digital Equipment Corporation.
              ERAQ.COM written by ?
              TYPE17.COM writen by Dave Rand.
              XDIR written by ?

: How to use.

              1.  d>PATCHCPM<cr>
              2.  PATCHCPM asks "Need help (Y/N)?"
              3.  Answer 'Y' for details.

: How to modify.

              PATCH.ASM  should  be  adequately self-documented to aid
         you in making any modifications.  Keep in mind  that  it  was
         purposely  written  in  8080  code  and  please read the help
         section "Features and Limitations."  Please let  me  know  if
         you come up with some other useful patches.

: Features and limitations.

         1.   This  program  cannot  load  past  08FFH or it will
              overwrite the memory image of the CP/M  system  you
              are patching - if necessary then remove some of the
              less useful patches to include yours.

         2.   If you answer 'N' to a question it will NOT restore
              the  CCP  to  it's  original state.  If you wish to
              remove the patch(s) then start with a "fresh"  CP/M
              system.

         3.   Note  that  if  you  disable  one  of  the built-in
              commands you must have a .COM file of that name  on
              the disk for that command to work.  For example you
              may  want to disable the built-in "DIR" command and
              put "SD.COM" renamed to "DIR.COM" on the disk.

         4.   This program was purposely written in 8080 code  so
              that all can use.
