Tuesday, February 17, 2009

From Clipper to Harbour - Viktor Szakáts

Date : Mon, 16 Feb 2009 10:40:57 +0100
Subject : Re: Long time no see

VICTOR : Hi Chong Hwa,
Nice to see you reviving Clipper...Clipper...Clipper.
It's been a long time :) I hope you're well.

CCH: Well, it's been more than 10 years :-)

VICTOR : Yep. I'm glad you remember.

VICTOR : If you're interested, I invite you to join Harbour's developer list,
it'd be great to see you there.

CCH: TQ and I am honoured by your invitation.
However, work commitments does not me to do so :-)

VICTOR : I can understand that, you're welcome any time in the future.

CCH: I would love to publish an article from you showing how you switched
from Clipper to Harbour. I am OK with xHarbour but I must admit I am a little lost on how to do it with Harbour.

From Clipper to Harbour - Viktor Szakáts

From a user's POV they are probably the same. Maybe there are some aspects of xhb which I don't know and could make the process different, but normally it's just a recompile and relink, feature-wise Harbour is on par with xhb, and a plus Harbour is cleaner, more robust, more portable and faster, it also has an xhb.lib which aims to provide compatibility with
features we've opted not to include in the core product.

I've just finished a new hbmk (Harbour Make) utility this weekend.

My transition was a long, gradual process, while keeping continuous Clipper releases and focusing on minimizing any risks on the user side, while maturing the Harbour release versions.

Also, the process was two fold:

1) Transition to Harbour for Windows.

2) Transition to be multi platform in general, allowing
easy move to any other platforms in the future.
This mostly comes down to file system / OS environment

Here are the main stages (and the devils are in the details :):

1) Departing from DOS/Windows concepts like case-insensitive filenames, drive letters and any other possible platform dependencies, like using some specific external tools. This was done by keeping Clipper compatibility, where this was impossible it was added using conditional code.

2) Some libs/tools which didn't have a Harbour/portable version, had to be replaced by new parts and sometimes concepts. One such is Telepath(y), which got replaced by curl, then hbcurl.

3) Adjusting all own .c functions for Harbour Windows version, using conditional code.

4) Added simple make system for Harbour Windows versions.

5) Created first running Harbour version for Windows and started testing locally plus a few clients.

6) After filling all missing bits in Harbour, there was time for the show to begin by creating the first official Harbour builds of the apps. Points below took 3-6 months depending on how we count it.

7) This quickly turned out to be a success since as apps were proved to run very stable, now the main work could begin by now being able to drop all Clipper heritage.

8) Created new local build systems for all parts, this time keeping in mind Linux/Darwin compatibility.

9) Started optimizing speed by refining the compiler choice and Harbour and local app build options.

10) After removing dependency on Clipper, the code could be moved from Clipper compatibility mode to Harbour native mode. This allowed to drop many functions and replace them with Harbour functions, tools and libs. This solved some rare problems with the apps, caused by bugs in local .c code. In fact I've reduced local .c code to an absolute minimum. This stage also resulted in noticeable speed up in certain points of the application.

11) The apps were now ported to Linux/Darwin with minimal effort.

12) Now fun part could be started, really start to exploit the possibilities of the new platforms and Harbour. I'm doing this since months and it's really a breath of fresh air.

Since I'm a main contributor to Harbour, all this was accompanied by parallel Harbour development, fixing incompatibilities, some bugs, finding all missing points and filling the gaps, and creating stable releases.

In the last few years the main areas to fill were TBROWSE, some multi-platform file handling stuff for the most part, and some stuff related to codepages. Currently using the latest SVN, which is practically release quality.

I hope that helps or is useful in any ways.


Viktor Szakáts

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Welcome to Clipper... Clipper... Clipper

In 1997, then using Delphi 3, I had already created 32-bits Windows applications for HRIS, ERP and CRM. In 2007, using Ruby on Rails, an AJAX powered CRM site running on Apache & MySQL was created and I am now using Visual Studio .Net 2008 to create web-based projects and Delphi 7 for Win32 applications using SQL2005 & DBFCDX.

So, why then am I reviving the Original Clipper... Clipper... Clipper via a Blog as CA-Clipper is a programming language for the DOS world ? Believe it or not, there are still some clients using my mission-critical CA-Clipper applications for DOS installed in the late 80's and up to the mid 90's. This is testimony to CA-Clipper's robustness as a language :-)

With the widespread introduction of Windows 7 64-bits as the standard O/S for new Windows based PCs & Notebooks, CA-Clipper EXE simply will not work and it has become imperative for Clipper programmers to migrate immediately to Harbour to build 32/64 bits EXEs

Since 28th January 2009, this blog has been read by 134,389 (10/3/11 - 39,277) unique visitors (of which 45,151 (10/3/11 - 13,929) are returning visitors) from 103 countries and 1,574 cities & towns in Europe (37; 764 cities), North America (3; 373 cities) , Central America & Caribeans (6; 13 cities), South America(10; 226 cities), Africa & Middle-East (12; 44 cities) , Asia-Pacific (21; 175 cities). So, obviously Clipper is Alive & Well : -)

TIA & Enjoy ! (10th October 2012, 11:05; 13th November 2015)

Original Welcome Page for Clipper... Clipper... Clipper

This is the original Welcome Page for Clipper... Clipper... Clipper, which I am republishing for historical and sentimental reasons. The only changes that I have made was to fix all the broken links. BTW, the counter from counter.digits.com is still working :-)

Welcome to Chee Chong Hwa's Malaysian WWW web site which is dedicated to Clipperheads throughout the world.

This site started out as a teeny-weeny section of Who the heck is Chee Chong Hwa ? and has graduated into a full blown web site of more than 140 pages (actually hundreds of A4 size pages) ! This is due to its growing popularity and tremendous encouragements from visiting Clipperheads from 100 countries worldwide, from North America, Central America, Caribbean, South America, Europe, Middle-East, Africa and Asia-Pacific. Thanx Clipperheads, you all made this happen !

What is Clipper ?

You may ask, what is this Clipper stuff ? Could Clipper be something to do with sailing as it is the name of a very fast sailing American ship in the 19th century ?

Well, Clipper or to be precise, CA-Clipper is the premier PC-Software development tool for DOS. It was first developed by Nantucket Corporation initially as a compiler for dBase3+ programs. Since then, CA-Clipper has evolved away from its x-base roots with the introduction of lexical scoping & pre-defined objects like TBrowse. As at today, the most stable version ofClipper is 5.2e while the latest version, 5.3a was introduced on 21 May 1996.

As at 11th November, 1996, an unofficial 5.3a fixes file was made available by Jo French. See the About CA-Clipper 5.3a section for more details. BTW, Jo French uploaded the revised 5.3a fixes file on 20th November, 1996.

Latest News

The latest news is that CA has finally released the long-awaited 5.3b patch on 21 May, 1997.

For 5.3b users, you must a take a look at Jo French's comments on unfixed bugs in 5.3b.

BTW, have you used Click ? If you're a serious Clipperprogrammer and need an excellent code formatter, Click is a natural choice. How to get it ? Simple, access Phil Barnett's site via my Cool Clipper Sites.

32-bits Clipper for Windows ?

Have you tried Xbase ++ ? Well, I have and compared to Delphi (my current Windows programming tool of choice), I'm still sticking to Delphi.

Anyway, you should visit the Alaska Home Page. Give it a chance and then draw your own conclusions !.

The Harbour Project

Is this the future of Xbase ? Take a look at at the Harbour Project

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