**************************************
*                                    *
*  Write Error Sentinel              *
*  by John Eidsvoog                  *
*  Copyright 1990 CodeHead Software  *
*                                    *
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Release date: Friday, March 2, 1990


What it is
----------

Write Error Sentinel is a memory-resident program which monitors disk
writing and will inform you with an alert box if there is a write error. 
There are a few instances and two in particular where there is no
warning given when you run out of free disk space. 

One particular danger is with ARC602.TTP which will not inform you if
you run out of room.  It's easy to delete an ARC file before you
realize you haven't extracted its files correctly.

Another case is when saving a capture file with a Flash! .DO file.  A
message appears on the bottom line but is immediately overwritten by the
next command in the .DO file.  With the Sentinel installed, you'll get
an alert box making sure you've seen the message. 

Considering that Write Error Sentinel uses less than 1K of your memory,
it is a valuable addition to your AUTO folder.


How to set it up
----------------

Simply copy SENTINEL.PRG into your AUTO folder.  It must run after
FATSPEED.PRG or POOLFIX3.PRG if you are using either of these. 
Otherwise it can be anywhere in your AUTO folder.  You'll see a small
message when Sentinel installs.  You can also install (run) SENTINEL.PRG
from the desktop.  That's it...once installed, it just sits and watches. 


How it works
------------

Write Error Sentinel watches for GEMDOS Fwrite calls.  GEMDOS returns
from the call, reporting the number of bytes that were written.  If this
number doesn't match the number of bytes requested to be written, the
Sentinel reports it to you with an alert box stating:

               ------------------------------------
              |  ____   THE SENTINEL REPORTS:      |
              | /    \  An error has occured while |
              | |STOP|  writing to this disk.      |
              | \____/  The disk may be full.      |
              |                                    |
              |                ----                |
              |               | OK |               |
              |                ----                |
               ------------------------------------

You should realize that many or most times this happens you will get two
error messages; one from the Sentinel, and one from the program doing
the writing.  Luckily, this does not happen very often.  Most disk
errors are detected at the file creating and opening level and the
Sentinel will ignore these.  The main type of error caught by the
Sentinel is insufficient disk space. 

For me it is well worth a few extra error messages if it will save me
some of the aggravation I've had when I wasn't warned at all. 


POINTS TO NOTE:
---------------

Remember that the Sentinel reports whenever the number of bytes requested
to be written doesn't match the number actually written.  It doesn't
necessarily mean that the disk is full, but if there is an attempt to
write more bytes than a disk has free, the Sentinel will always report.

In some programs (such as ARC602.TTP) you may get Sentinel's alert box
with no mouse arrow to click OK.  Just hit Return or Enter (or play the
game of searching with the mouse button held down :-).


Copyright stuff
---------------

SENTINEL.PRG, and this document are Copyright 1990 CodeHead Software. 
However, they may be freely distributed as long as this text file and
the Write Error Sentinel program file are both included.  Neither this
document file (SENTINEL.TXT) or the program file (SENTINEL.PRG) may be
altered in any way.  Copies of these files may not be sold, and this
document may not be reprinted, without the express written permission of
CodeHead Software. 

We've tried to make Write Error Sentinel as bug-free as possible. 
Nevertheless, CodeHead Software cannot be responsible for any damages
that may occur as a result of the use (or misuse) of Write Error Sentinel.