FRONTSUB.DOC

                    (c) 1986 by Claude Ostyn
                    Supplement to FRONT51.DOC

                            CONTENTS:

          1.  SPECIAL INSTRUCTIONS FOR THE USE OF
              FRONT WITH REPEAT OPTIONS 2 OR 3

          2.  HOW FRONT REPEAT OPTIONS 2 OR 3 WORK
 
                              -----

1.  SPECIAL INSTRUCTIONS FOR FRONT WITH REPEAT OPTIONS 2 OR 3

If you select option 2 or 3 to make FRONT run again automatically 
after executing a command, you will have to follow these simple 
rules.  If something goes awry, look up these rules and you may 
find out that you did something that was in contradiction with 
them.  Don't panic!  Nothing very wrong can happen.

-  FRONT.COM (under any name you chose during installation) must 
   be on the disk in drive A.  SUBMIT.COM is NOT required.

-  The disk in drive A must not be write-protected;  if it is 
   write-protected or full, you will get an error message.

   If you get an error message after you see

          "EXECUTING (your command)"

               - Don't panic.  It's not as serious as it looks.
                 Under CP/M 2.2, you may get a "Bad Sector"
                 error, but there is no bad sector.  It only 
                 means that Bdos was not able to write something
                 on the disk and used its catch-all message.
               - Press RETURN (or "i" if using CP/M Plus).
               - In the unlikely event that, after you press 
                 RETURN, you get a another "Bad Sector" message, 
                 then you may begin to panic:  there may indeed 
                 be something wrong with your disk.
               - You will see a message saying "Disk full or R/O:
                 Unable to proceed".
               - FRONT will now exit to CP/M without executing
                 your command.  Usually, this error happens 
                 beacause the disk in drive A (with option 2) or 
                 in the current drive (with option 3) has a 
                 write-protection sticker or is full.  Front 
                 needs to write one file of minimum size (1K to 
                 8K, depending on your system) if working within 
                 the same user area, and two files if working 
                 within different user areas. 

-  If you want to return to FRONT after changing the disk in 
   drive A (for instance if you were using NSWEEP), put the disk 
   which was originally in drive A back into drive A.  

   Do this BEFORE you exit the called program.  

   If the original disk is not in drive A, FRONT will simply not 
   run again automatically, but if you later put that original 
   disk back in drive A, FRONT will try to run again at the first 
   opportunity.

-  If you use .SUB files with SUBMIT.COM, the last command in the 
   .SUB file should be A:FRONT (or the name you gave FRONT during 
   installation).  This is not necessary if you use EX14.COM to 
   run your .SUB file. 

-  If you do NOT want to return to FRONT, you can interrupt the 
   execution of the $$$.SUB by just pressing the space bar.

-  If you want to look at the screen before returning to FRONT at 
   the end of your program, type ^S (Control-S) to pause.  Type 
   ^S again to continue.  Do NOT press any other key unless you 
   do not want to run FRONT again.


2.  HOW FRONT REPEAT OPTIONS 2 AND 3 WORK

  At every warm boot, the CCP looks for a file named $$$.SUB on 
drive A, executes the command contained in the last record in 
that file and then deletes that record from the file.  The next 
time CCP looks at the file, if it finds it empty (no more 
commands to execute) it just erases it.

  When FRONT executes the command you selected from the menu, it 
first tries to create such a $$$.SUB file containing the name 
under which FRONT was saved by FRNSTL46 (the name might be FRONT, 
FRONT46, MENU, or whatever).  This file also contains the command 
USER xx, where xx is the current user area, to ensure that CP/M 
will return to the same user area you were looking at with FRONT.

  The $$$.SUB file is created on drive A in user 0 under CP/M 
Plus and on drive A in the current user under CP/M 2.2.  It is 
also set to SYS, so it does not show on a normal directory but 
can be found and executed by CP/M Plus.

  When the called program returns to CP/M, the CCP finds the 
$$$.SUB file, returns to the original user area, reloads FRONT 
and erases the .SUB file.  Note that the file SUBMIT.COM is not 
required anywhere at any time for this process. 

  If you use SUBMIT.COM to run another .SUB file from the menu, 
FRONT does not create a $$$.SUB file since the first thing SUBMIT 
would do would be to erase it when it creates its own $$$.SUB.  
For this reason, the last command(s) in a .SUB file to be used 
with the standard SUBMIT.COM should be A:FRONT (or whatever name 
under which FRONT exists), possibly preceded by a command to 
return to the FRONT user area.

  If your CCP has been replaced by a recent version of ZCPR which 
requires that you select auto-repeat option 3, read "current 
drive" instead of "drive A" in the paragraphs above.

Special note for SUBMIT file writers:

  FRONT assumes the current logged drive/user is where you want 
to read the menu from (unless otherwise installed).
  However, it accepts a user number as an argument.  The number 
MUST be two digits.  You will see that feature at work when the 
$$$.SUB is executing;  it allows FRONT to return to the same 
drive/user from wich a command was selected.

Examples (assuming ZCPR with user area shown in system prompt):

               A9>FRONT 01  
                    will list commands from drive A, user 1

               A9>FRONT 1 
                    will list commands from drive A, user area 9
                    (only one digit in user parameter--illegal)

             
3/30/86