README.compat

2.2 compatible version
----------------------

Since becoming open sourced on Linux and other free platforms, a number of incompatibilities have arisen
between the originally experimental version 2.2.x and the 2.1.x series that is closest to Motif on other platforms,
and contains many bug fixes that are not in 2.2.x

These incompatibilities meant that an application could not use the robust 2.1.x Motif if it required prebuilt widget
libraries such as XRT that had been built with 2.2 (the default Motif on Linux distros).

If you follow the instructions below, you can build a version of 2.1.x that is object compatible
with Motif-based libraries that were built with 2.2

The version is quite safe. It does two extra things:

	* it pads the Motif data structures so that they are identical to those in 2.2
	* it uses the 2.2 XmString data files for generation of XmString tables


1. To build the compatible version, he following environment variables need to be set

export USERCFLAGS="-DM222i=1"
export USERVARIANT="-22i"
export USER_IMAKE_DEFINES="-DM222i=1"
export DEFINES=${USER_IMAKE_DEFINES}

2. Once you install the distribution, you need to replace all of the

#ifdef M222i

lines with

#if 1 /* M222i */

since Motif users will not be using the -DM222i compilation flag.

The files that need changing are:

include/Xm/DropSMgrP.h
include/Xm/GadgetP.h
include/Xm/MenuShellP.h
include/Xm/PrimitiveP.h
include/Xm/VendorSEP.h
include/Xm/Xm.h