LSH, Version 1.10  Update
August 25, 1991


FIXED LOG VERSION

     There is now a separate version of LSH which uses a fixed size 
history file.  Its purpose is to speed up operation on floppy disks, 
or even hard disks, by allowing you to place the history file on the 
outer disk tracks (i.e. it will be one of the first files on the disk) 
and know that it will STAY there.  The Variable Log version keeps 
adding to the history indefinitely, so you will eventually end up 
reading from the inner tracks.

     A new history file, or an old one which is shorter than the 
nominal length, is padded to the full size.  When the history is full, 
only the end of the file is written to disk.  You lose the first 
command lines.

     The file size is installed with LSHINST.  The distributed version 
reserves 4k, but 2k may be all you need.

CAUTION:  If you edit a history file independently, the text editor 
will probably truncate it.  However, if LSH runs immediately 
afterward, it will pad the file back out to its reserved length 
when you execute the next command.



COMMAND COMPLETION

     Idea taken from PCED:  When completing the first token on the 
line, only .COM types are matched (along the path), and a trailing 
space is appended.  Then you are immediately ready to add command 
arguments.  For example:

     c<COMMAND COMPLETE>
     cl <AGAIN>
     crunch
then...
     crunch f<COMMAND COMPLETE>
     crunch foo.com<AGAIN>
     crunch foo.z80
     
     Command Complete now recognizes "=" and "," as token 
separators, so it works on argument lists and for CP, REN, etc.  
It also now handles lines starting with ":" or "." to force 
search of current directory on first token.


LINE SEQUENCING

     A review of old messages about LSH reminded me that someone 
wanted the automatic line sequencing command to return to the same 
line rather than go to the next line.  LSHINST can now configure that 
choice.  It cannot be toggled within LSH.


SINGLE INVOCATION

     The command line now has a /C option to run LSH once.  This is a 
convenience when you want to dig up an old command line, but don't 
want the shell running.


USER ROUTINE

     A small user's routine can be installed in a 32 byte patch area.  
The code there is run when the User Patch key is pressed.  The patch 
must end with RET if LSH is to keep running.  All registers are 
available for your use.

     Code can be assembled to an object file and overlayed on LSH with 
BCOMP.  The patch area is surrounded by "USR> ..patch.. <USR" markers. 
You can also enter hex code directly with LSHINST.

     The patch could be used to send a terminal or printer init 
string.  Another possibility is a system specific patch to turn the 
printer on and off.  It does not work to use the usual ^P because the 
editor does not input characters via BDOS function 2.  (Embedding ^P 
in a command line does not work either.)


; Sample printer toggle user routine

dospat	  equ  0d628h	 ; Printer toggle location (in my DOS, not yours!)

patch:    ld   a,(dospat)    ; Get state
          cpl                ; Flip it
          ld   (dospat),a    ; Store it
          ld   e,7           ; Beep
          ld   c,2           ; Char out
          jp   5

	if ($-patch) gt 32
*** TOO BIG ***
	endif
          end


CODING CHANGES

1.   In previous versions, the line editor would warm boot on ^C.  
This version warmboots (in Line Mode only) when the "screen down" 
command is pressed.  That is still ^C for a WordStar-like 
installation, but could be something else after running LSHINST.  You 
can also get a warmboot using ESC C, just as for Screen Mode.
(This change is a side effect of some consolidation of the two 
editors.)

2.   This version does not rely on the integrity of alternate regs 
across a call to CIN.

3.   The DUOK flag is checked before displaying prompt.

4.   Terminal installation has been removed.  The full screen divider 
line is now drawn with a call to VLIB routine GHBAR, if available.  
(This one routine added almost 3 records to LSH.  Worth it?)

5.   LSH is coded to run safely as Type3 or Type4 under ZCPR3.4.  
Those running ZCPR3.3 need to patch the first byte of the Type 3 
version to C3h (JP), rather than C7h (RST 0).  No Type 1 version is 
distributed.  I will be happy to assemble one for anyone who needs it.

6.   Screen mode now obeys the CLS flag setting when a line is 
executed with shell pause.

7.   Command Complete and Token Repeat control bindings are no longer 
required to be single keys.  It is OK to use meta-key/key combinations now.

8.   A half dozen small bugs were fixed.

9.   A new ZERRLSH, the error handler which corrects LSH's history file, 
is needed for the Fixed Log version.  I also recommend the newer error 
handler for the variable log version.  It signs on as ZERR+LSH, Version 
1.5d.  The error handler part is the same as ZERR 1.5, only the +LSH 
part is new.


Source code is available to hackers.  However, I am not uploading it. 
It runs over 150k and would be best distributed by disk.


Thanks to Bruce Morgen, Jay Sage, Gene Pizzetta for ideas on 
improving this version.

END LSH11.NEW