Porting from other UNIX platforms to Linux (64bit)

Hello,

can somebody please share the experiences from porting an application,
that exists on AIX, Solaris, HPUX (64bit) and IRIX, to Linux (64bit)?

The special thing about this applications is, that it uses MOTIF v1.2
and tcl.

Can we simply transfer our make environment to the Linux Workstation,
modify the compiler and linker (switches) to the standard Linux
compiler/linker and round it goes?

What's about building tcl?

We had problems in the past to build it on the mentioned UNIX
platforms.

Another important questions is, how to handle the licences from
external libraries!

Our software was and will be always commercial software, so using GPL
licenced libraries would turn things upsite down, right?
We read some papers about the GPL licences, but we are  about
the consequences, when using (L)GPL licenced libraries!
Currently it is really simple! We bought all the software, the
licences of the libraries we use!

I would really appreciate experience reports, comments, ...!

Best regards,

Martin Lemburg
UGS The PLM Company (formerly known as Unigraphics Solutions)

According to Martin Lemburg <martin.lemburg.ugs@gmx.net>:
:can somebody please share the experiences from porting an application,
:that exists on AIX, Solaris, HPUX (64bit) and IRIX, to Linux (64bit)?

I've done some porting from Solaris to GNU/Linux - but not 64 bit.

Does your application currently work in 64 bit environments?  If not,
then you have two ports - one from OS to OS and the second from 32 bit
to 64 bit.  Certainly you can do both simultaneously.  But if you
could do the 64 bit port on your existing platform - say Solaris -
then you would know you only had to worry about 64 bit issues and not
an unknown OS.

:The special thing about this applications is, that it uses MOTIF v1.2
:and tcl.

Hmm - are you using the old SCO "visual tcl" toolkit ?
Note that another fun thing you may have is getting MOTIF 1.2 to
go on GNU/Linux.  But maybe someone else has already done that.


:Can we simply transfer our make environment to the Linux Workstation,
:modify the compiler and linker (switches) to the standard Linux
:compiler/linker and round it goes?

Depends - what is your make environment?  Do you use gcc?  Do you
use any special libraries?

Also, if I were involved with such a project, I'd expect to find that
some function calls or function return values differed on GNU/Linux 64
bit (things that depend on size of time_t, size_t, etc. like ls, etc.)

:What's about building tcl?

Well, building Tcl shouldn't be an issue.  What you WILL find, though,
is that if you try to depend on one vendor's build of GNU/Linux, you will
have difficulty.  I won't mention the vendor, who has traditionally used
a brightly colored Fedora as a logo...


:We had problems in the past to build it on the mentioned UNIX
:platforms.

There shouldn't have been problems - you should have asked around here.
Tcl itself should build find on those platforms.  However, some of
those platforms have certain system software which cause all software
developers problems.  Perhaps you encountered some of those problems.

:Another important questions is, how to handle the licences from
:external libraries!

:Our software was and will be always commercial software, so using GPL
:licenced libraries would turn things upsite down, right?

Seems to me that you are already in this mess - I mean, the license
isn't OS specific - the software you are using has the same license on
Solaris as it does on GNU/Linux (in all likelihood).

I'll bet your concern is whether the GNU/Linux libraries will
cause licensing conflicts for your commercial application.

Hopefully someone will address this
--
<URL: http://wiki.tcl.tk/ > In God we trust.
Even if explicitly stated to the contrary, nothing in this posting
should be construed as representing my employer's opinions.
<URL: mailto:lvirden@gmail.com > <URL: http://www.purl.org/NET/lvirden/ >

Martin Lemburg wrote:

> can somebody please share the experiences from porting an application,
> that exists on AIX, Solaris, HPUX (64bit) and IRIX, to Linux (64bit)?
>
> The special thing about this applications is, that it uses MOTIF v1.2
> and tcl.

Tcl runs on all of those environments just fine.  With the
exception of IRIX, those are all actually supported enterprise
platforms at ActiveState.

> Can we simply transfer our make environment to the Linux Workstation,
> modify the compiler and linker (switches) to the standard Linux
> compiler/linker and round it goes?
>
> What's about building tcl?

It depends on your compiler.  gcc will be your compiler on
Linux, but was that what you used before?  If so, you should
be golden, otherwise, you may have some work ahead.

> We had problems in the past to build it on the mentioned UNIX
> platforms.

As I said, we build it on all of the above (except IRIX), and
don't have issues.  Some extensions give us trouble sometimes,
but if they stick with the latest TEA, there are usually no
issues (and don't use C++ ... phthui!)

> Another important questions is, how to handle the licences from
> external libraries!
>
> Our software was and will be always commercial software, so using GPL
> licenced libraries would turn things upsite down, right?
> We read some papers about the GPL licences, but we are  about
> the consequences, when using (L)GPL licenced libraries!
> Currently it is really simple! We bought all the software, the
> licences of the libraries we use!

Using LGPL won't be an issue, you just have to stick to the
license terms and leave those bits open.  You likely can't use
GPL'ed work directly in your application codebase, but if you
aren't using it now, I don't know why you would add it.

gcc and the gnu build toolchain is what you will rely on for
building, but you don't get "infected" by the use of these GPL
tools simply by building with them.  Unless you are modifying
something in the architecture to use other libraries, I am not
sure why you are worried about other licenses.

--
Jeff Hobbs, The Tcl Guy
http://www.ActiveState.com/, a division of Sophos

> lvirden@gmail.com wrote in message news:<cgiaqs$mbr$1@srv38.cas.org>... 
> I've done some porting from Solaris to GNU/Linux - but not 64 bit.
>
> Does your application currently work in 64 bit environments?  If not,
> then you have two ports - one from OS to OS and the second from 32 bit
> to 64 bit.  Certainly you can do both simultaneously.  But if you
> could do the 64 bit port on your existing platform - say Solaris -
> then you would know you only had to worry about 64 bit issues and not
> an unknown OS.

We actually had to support 32bit and 64bit builds. Our 64bit
environments are Solaris and HP-UX.

> :The special thing about this applications is, that it uses MOTIF v1.2
> :and tcl.
>
> Hmm - are you using the old SCO "visual tcl" toolkit ?
> Note that another fun thing you may have is getting MOTIF 1.2 to
> go on GNU/Linux.  But maybe someone else has already done that.

No, no - our application started originally with tcl 7.0 and the GUI
was completely built in MOTIF 1.2.
The widgets have commands/callbacks in/to tcl. So our GUI has nothing
to do with tk or "Visual Tcl".
Our widget "system" is very old and stable, so it won't be changed if
not really needed!
Even on MS Windows we used MFC dialog components to build our
application specific needed widgets and exported them via tcl commands
and tcl callbacks!
So our tcl application sees no difference between UNIX and MS Windows.

Yes, we didn't use tk and we won't use! tcl/tk didn't and won't
support OpenGL canvas in the core. And so we would have needed to use
external tcl extending libraries like togl.
The decision is made 8 years ago and the consequences will last the
next 8 years for sure! :-(

Perhabs we can switch with not too much amount of work to MOTIF 2.x,
but ... we use a lot of X-stuff, so we think to switch while porting
to Linux to another Windows Toolkit like e.g. Qt.

> :Can we simply transfer our make environment to the Linux Workstation,
> :modify the compiler and linker (switches) to the standard Linux
> :compiler/linker and round it goes?
>
> Depends - what is your make environment?  Do you use gcc?  Do you
> use any special libraries?

Our build environment uses the platform specific native compiler and
linker.
We have company wide rules what compiler and linker, switches, options
have to be used on the supported platforms.
And ... due to the fact, that we have executables linked with external
libraries that expect special compilers/linkers with special verions
(mostly old and hard to get versions) ... we are not able to use gcc
on AIX and IRIX.

For builds on Linux, we are due to the missing company wide build
rules free to use what we want and perhabs to set company standards!
And ... on Linux we won't have to include "special" external
libraries.

You think I talk confusing things! Yes - it is that way!

> :We had problems in the past to build it on the mentioned UNIX
> :platforms.
>
> There shouldn't have been problems - you should have asked around here.
> Tcl itself should build find on those platforms.  However, some of
> those platforms have certain system software which cause all software
> developers problems.  Perhaps you encountered some of those problems.

We had problems, because our UNIX machines are quite old and not
really up to date. And even the up to date HP machine made problems.
We never could build tcl the simple way: running configure with wanted
options, running make, finished!
Never!

And I often asked for help in the newsgroup and got none.
The only answers came from Jeff Hobbs mentioning the library build
service from ActiveState.
But do you think my company is willing to pay for such services?

But I forgot that ActiveState has a Linux distribution. For MS Windows
we already use the ActiveState distribution.

> :Another important questions is, how to handle the licences from
> :external libraries!
>
> :Our software was and will be always commercial software, so using GPL
> :licenced libraries would turn things upsite down, right?
>
> Seems to me that you are already in this mess - I mean, the license
> isn't OS specific - the software you are using has the same license on
> Solaris as it does on GNU/Linux (in all likelihood).

Currently we don't use consiously any GPL libraries.

We bought the development environments with the UNIX OS' and used
them. That's all.
And we have only dependencies to OpenGL, MOTIF and our own simulation
toolkit. Ok, perhabs to external CAD software libraries, but only on
some platforms.

> I'll bet your concern is whether the GNU/Linux libraries will
> cause licensing conflicts for your commercial application.

Yes!

I've taken a look on a Linus distribution to see e.g. if MOTIF is
distributed. And I found a (L)GPL version, OpenMotif. So I started to
think over and think that we could have troubles!

But in the next w our company has to think over the way to port
applications to Linux, the supported Linux distribution(s) and the
sources of external libraries and their licences.
So it will be, not our (little software developer) problem. It will be
a company wide problem, to be solved by managers and lawers.

> Hopefully someone will address this

Thanks (for your emails too)!!!

Best Regards

Martin Lemburg

Jeff Hobbs <jeffh@removethis.activestate.com> wrote in message news:<412CC335.3040001@remov
ethis.activestate.com>...
> Martin Lemburg wrote:
>
... snip ...
> 
>
> It depends on your compiler.  gcc will be your compiler on
> Linux, but was that what you used before?  If so, you should
> be golden, otherwise, you may have some work ahead.

We used on each platform the specific "native" compiler/linker. Only
if we had to link with e.g. CAD software libraries, we had to use
compilers/linkers wanted by those libraries.

The problem is, that we have company wide build rules, specifiying for
each platform the compiler/linker to be used and their
switches/options.
Those rules rely only on comercial development environments, so that a
special support and warranty is guaranteed.

So - we "have some work ahaed"!
 
>
> As I said, we build it on all of the above (except IRIX), and
> don't have issues.  Some extensions give us trouble sometimes,
> but if they stick with the latest TEA, there are usually no
> issues (and don't use C++ ... phthui!)

We had on each platform issues. Perhabs you remember our eMail
communication about the ActiveState library build service?

And - we use ANSI C++ where ever its possible! And we have no problems
with C++ and tcl, but more with not-up-to-date-machines and perhabs
wrong configured machines!
e.g. the configure scripts are mostly not able to detect the time zone
handling.
 
>
> Using LGPL won't be an issue, you just have to stick to the
> license terms and leave those bits open.  You likely can't use
> GPL'ed work directly in your application codebase, but if you
> aren't using it now, I don't know why you would add it.
>
> gcc and the gnu build toolchain is what you will rely on for
> building, but you don't get "infected" by the use of these GPL
> tools simply by building with them.  Unless you are modifying
> something in the architecture to use other libraries, I am not
> sure why you are worried about other licenses.

Thanks!
So we have to make or managers spend money in buying e.g. MOTIF, so
that we are not in the need to use OpenMOTIF (LGPL). We'll see how
generous they are.

Thanks and best regards,

Martin Lemburg

According to Jeff Hobbs  <jeffh@removethis.activestate.com>:
:> Another important questions is, how to handle the licences from
:> external libraries!

:Using LGPL won't be an issue, you just have to stick to the
:license terms and leave those bits open.  You likely can't use
:GPL'ed work directly in your application codebase, but if you
:aren't using it now, I don't know why you would add it.


Okay - having never developed a commercial product on Linux, I can
see I have a similar confusion.

So, tell me about the GNU/Linux C development environment as shipped
on the standard distributions.  If I am compiling and linking my
employer's commercial code on a GNU/Linux system, are there some
standard libraries that might result in the source being forced
to be made available?  Are the GNU/Linux libc runtimes, etc. all
covered by licenses that make it possible to do what Martin and others
are trying to do?  Or do commercial developers have to purchase special
any special replacement libraries?

--
<URL: http://wiki.tcl.tk/ > In God we trust.
Even if explicitly stated to the contrary, nothing in this posting
should be construed as representing my employer's opinions.
<URL: mailto:lvirden@gmail.com > <URL: http://www.purl.org/NET/lvirden/ >

lvirden@gmail.com wrote:

> According to Jeff Hobbs  <jeffh@removethis.activestate.com>:
> :> Another important questions is, how to handle the licences from
> :> external libraries!
>
> :Using LGPL won't be an issue, you just have to stick to the
> :license terms and leave those bits open.  You likely can't use
> :GPL'ed work directly in your application codebase, but if you
> :aren't using it now, I don't know why you would add it.
>
> Okay - having never developed a commercial product on Linux, I can
> see I have a similar confusion.
>
> So, tell me about the GNU/Linux C development environment as shipped
> on the standard distributions.  If I am compiling and linking my
> employer's commercial code on a GNU/Linux system, are there some
> standard libraries that might result in the source being forced
> to be made available?  Are the GNU/Linux libc runtimes, etc. all
> covered by licenses that make it possible to do what Martin and others
> are trying to do?  Or do commercial developers have to purchase special
> any special replacement libraries?

No, the gcc build tools and libraries specifically allow for
building your commercial tools without license restrictions.
This is true for gcc on any platform.  Otherwise gcc would not
have been so popular (and/or Linux would never have made it to
where it is today).

--
Jeff Hobbs, The Tcl Guy
http://www.ActiveState.com/, a division of Sophos

Martin Lemburg wrote:
> So we have to make or managers spend money in buying e.g. MOTIF, so
> that we are not in the need to use OpenMOTIF (LGPL). We'll see how
> generous they are.

I don't see why you have to buy Motif, as OpenMOTIF and the LGPL
license should be a compatible license in your application.  You
just have to be careful about abiding by the open license terms
for that part, but LGPL isn't viral.

--
Jeff Hobbs, The Tcl Guy
http://www.ActiveState.com/, a division of Sophos