On 11/08/2017 11:58 AM, Serguei Mokhov wrote:
> On Wed, Nov 8, 2017 at 12:46 PM, Yasha Karant <[log in to unmask]> wrote:
>> I know at one time that there was a proprietary (licensed for fee)
>> development environment that was native and portable to X11, Mac OS, and MS
>> Win -- that is, using this "magic" set of libraries, etc., the same source
>> code (ANSI C++ base as I recall) would have the same GUI interface in the
>> developed application on all three of these.  I do not recall for which
>> releases this worked.  (My assumption is that there must be something still
>> like this as many "major" web browser applications have variants for each of
>> these different environments.)
>>
>> In a similar way, but hopefully open systems (not licensed for fee), is
>> there a lowest common denominator for Linux that will work on both Red Hat
>> and Debian based distros (e.g., SL, Fedora, etc., and Ubuntu, Mint, etc.)?
>> -- not necessarily the latest and greatest, but write once (preferably in
>> ANSI C++ current GNU production release), compile on each environment, and
>> run.   I know that this works for various interpreters (e.g., java, python)
>> -- but we are looking for compiled to physical machine code if possible.
> 
> Qt?
> 
> https://en.wikipedia.org/wiki/Qt_(software)
> 

Technically Qt, GTK, and motif all fit this need in some fashion.  I 
will agree that Qt probably supports the largest diversity of platforms.

Python, TCL, and a bunch of other scripting languages have Qt libraries 
as well as things like TK.