Program:        SNAP, Version 1.2
Author:         Rob Friefeld
Purpose:        Save image of Z-System packages into a reloadable file.
Date:           26 Mar 1990

Syntax:         SNAP file[.typ] /oo...
                o = (T)cap, (R)cp, (F)cp, (I)op, (N)dr, or (P)ath

-------------------
Version 1.2
     - uses internal stack  (lack of one caused a crash with Kaypro Turbo ROM)
     - new command line options ... see below
-------------------

     SNAP saves an image of the ENV, TCAP, RCP, FCP, IOP, NDR, and 
PATH together with a small loader to the file named on the command 
line.  For further flexibility, command line options permit saving 
only the segments wanted.

     SNAP is NOT a package relocator.  It just plugs a package setup 
back into memory where it presumably came from.  If you load a snap 
into an incompatible system configuration, you will crash.  (With 
NZCOM, use NZBLITZ or JETLDR.)

Usage:
        SNAP SYS         ; Save current packages to file SYS.COM
        LDR OTHER.ENV,OTHER.RCP,OTHER.NDR,OTHER.FCP
        SNAP OTHER       ; Save this version to OTHER.COM
        SYS              ; Reload all original packages at once.
        OTHER            ; Run the other configuration.
        SNAP OTHERNDR /N ; Save only NDR

     SNAP particularly speeds up the system cold start.  Individual 
segments also load very quickly when stored as executable files.

     A patch byte at 10Dh (800Dh for CIM file) may be set to 00 to 
cause SNAP to erase an existing file without warning.  As distributed, 
SNAP will ask whether or not to erase an existing file.  The default 
list of segments to be automatically saved can be configured.  (Use 
SNAP12.CFG with ZCNFG.COM by A. Hawley.)

     The package loader does some mininal error checking before 
overwriting memory.  It makes sure that the current ENV descriptor is 
at the same location as the one about to be loaded.  If an extended 
environment has been installed, the loader then checks to see that the 
CCP, BDOS, and BIOS have not moved.  Finally, if only a few segments 
have been saved, the loader insists that all of the ENV addresses be 
the same currently as when the snap was taken.  If all segments were 
saved, the user is allowed to load a differently configured system.  
This makes sense only if the large system packages (RCP, FCP, IOP, 
NDR) occupy contiguous memory and are of constant total size.


END SNAP12.DOC