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---------- Zinc Application Framework 5.3 - UPGRADE.TXT -------------
----------- COPYRIGHT (C) 1990-1999. All Rights Reserved. -----------
-------- Wind River Systems Incorporated. Alameda, CA, USA ----------
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This file provides information on the differences between ZAF 4 and
ZAF 5. It contains the following sections:

    General Information
    What About Existing ZAF 4 Projects

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--- General Information ---------------------------------------------
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ZAF 5 code is *not* backward compatible with ZAF 4. In an effort to
bring the product up to date and make it competitive with
non-portable tools, this change was required.

Conceptually, however, ZAF 5 is still very much the same. The
concepts you have already learned for ZAF 4 will serve you well,
reducing the learning curve to about one day according to our early
test sites.

A convert utility is supplied which will convert all ZAF 4 ".dat"
files to the new ZAF 5 ".znc" format. In addition, a simple
text-replacement utility, "rep4to5" is included to quickly replace
ZAF 4 symbols with ZAF 5 equivalents. Note however, this does not
actually convert code, but only replaces symbols. Parameter order,
logic changes, etc are required to fully complete conversion.

Examples of ZAF 4 programs converted to ZAF 5 are included in the
"convert" distribution files. ZAF 4 "Hello2" and "Agency" are
supplied, along with ZAF 5 converted code and descriptions of
individual changes required to convert the code.

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--- What About Existing ZAF 4 Projects? -----------------------------
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    1. Large Scale: If you have large-scale existing projects that
are already shipping or nearly so, we recommend that you continue
with ZAF 4 for those projects only. Converting code will bring you
better stability and performance, but the time required seems to be
about 1 man-day per 1000-1500 lines of code for initial conversion,
plus debug time. ZAF 5 projects are typically 20-30% smaller (less
source code), faster, and much easier to maintain.

    2. Smaller Scale: If you have smaller scale projects or are in
the early stages of development on a new project, the benefits of
converting your code will save you time in the long run.

    3. Unix: If you are doing *any* development with ZAF 4 for Motif,
we recommend that you convert immediately. The benefits in stability
alone will far offset any effort to convert.
