# BEGIN LICENSE BLOCK
# Version: CMPL 1.1
#
# The contents of this file are subject to the Cisco-style Mozilla Public
# License Version 1.1 (the "License"); you may not use this file except
# in compliance with the License.  You may obtain a copy of the License
# at www.eclipse-clp.org/license.
# 
# Software distributed under the License is distributed on an "AS IS"
# basis, WITHOUT WARRANTY OF ANY KIND, either express or implied.  See
# the License for the specific language governing rights and limitations
# under the License. 
# 
# The Original Code is  The ECLiPSe Constraint Logic Programming System. 
# The Initial Developer of the Original Code is  Cisco Systems, Inc. 
# Portions created by the Initial Developer are
# Copyright (C) 2006 Cisco Systems, Inc.  All Rights Reserved.
# 
# Contributor(s): 
# 
# END LICENSE BLOCK

ECLiPSe kernel initialisation
-----------------------------

Initialisation of eclipse happens in 3 phases:

    mem_init(init_flags)
    	initialise the memory management

    eclipse_global_init(init_flags)
    	initialise heap, dictionary, global tables, code, ...

    emu_init(init_flags)
    	initialise one abstract machine



The ..._init() functions have a flag argument specifying what has
to be initialized. These flags are bit-significant.


    INIT_SHARED
	Initialize the (possibly shared memory) heap, e.g. dictionary,
	procedure table and all related data structures.

    REINIT_SHARED
	The (possibly shared memory) heap was restored and some of its
	contents may need some adjustment.

    INIT_PRIVATE
	Initialize data that is not in shared memory, e.g. (private)
	global C variables. This is typically copied from shared memory.

    INIT_ENGINE
	Initialise the abstract machine. This flag is not really used currently.

    INIT_PROCESS
	Initialize things like signal handlers, I/O streams etc.
	This is the stuff that e.g. does not survive a saved state.



Flag combinations are for example:

INIT_SHARED|INIT_PRIVATE|INIT_ENGINE|INIT_PROCESS
	when starting an unbooted sepia

INIT_ENGINE
	reinitialising after a fatal signal was caught.

INIT_PRIVATE|INIT_ENGINE|INIT_PROCESS
	starting an unbooted sepia that shares its heap with
	an already running sepia process (-m mapfile option).



Note:  A lot of this rather complicated setup is a heritage of the
feature of "saved states" (dropped in release 3.6).  There were two
types of saved states, "program" saved states, and "execution" saved
states.  After restoring these states from file, the following
initialisation configuration was necessary:

REINIT_SHARED|INIT_ENGINE|INIT_PRIVATE
	after restoring a programm saved state, i.e. all global data
	is already initialised (from the saved state file)

REINIT_SHARED|INIT_PRIVATE
	after restoring an execution saved state, i.e. all global data
	and the engine are already initialised (from the saved state file)