Very Computer

OK, I've just looked through a copy of the GPL.  (I confess that I
didn't read the whole license thoroughly.)  And I am not sure whether
the GPL allows the following: I'm considering including a GPLed program
in a software package I will be releasing.  (The package is free
software (but not GPL), but I may charge for extensions to it in the
future.)  The GPLed program is a Perl script that will be used to
obtain data from a web site needed by my program.  My program, which is
a compiled executable, will probably use a fork and exec to execute the
Perl program and obtain the resulting data (from a file or whatever).
Also, my program will be written so that other scripts or programs can
be used - plugged in - instead of this GPLed Perl program.

My question is - in the above case, if I include the Perl program with the
release of my program, will my program need to be released under the GPL?
Since the Perl script is not a library being used by my program and is not
being extended to create my program's functionality, I would expect that
my program does not need to be GPLed; but I can't tell for sure from the
license.

The clause in the license that appears to apply to this case is:

    b) You must cause any work that you distribute or publish, that in
    whole or in part contains or is derived from the Program or any
    part thereof, to be licensed as a whole at no charge to all third
    parties under the terms of this License.

I think the interpretation hinges on what is meant by "contains", which
doesn't appear to be explicitly defined in the license.

If the answer to my question is that my software does indeed need to be
GPLed, what about if I release the software without the Perl program, but
include instructions for users who want to use that program as the "plug-in
data-retrieving script" - that they download it and set it up to work with
my program?

Thanks!
--
Jim Cochrane

Quote:> future.)  The GPLed program is a Perl script that will be used to
> obtain data from a web site needed by my program.  My program, which is
> a compiled executable, will probably use a fork and exec to execute the
> Perl program and obtain the resulting data (from a file or whatever).
> Also, my program will be written so that other scripts or programs can
> be used - plugged in - instead of this GPLed Perl program.

For safety I'd distribute the script seperately from your program, not
in the same tar file or whatever, just to make the seperation clear.

--
Collin was right. Never give a virus a missile launcher.
                                -- Erk, Reality Check #8

Anyway, I think I'm probably OK, though I wouldn't mind hearing from a
couple other people with knowledge of the GPL.

Quote:

>For safety I'd distribute the script seperately from your program, not
>in the same tar file or whatever, just to make the seperation clear.

Quote:Todd Knarr writes:
> I think this is covered explicitly in the GPL: merely including a GPLed
> program on the media with yours does not cause your program to be GPLed.

Quote:> From the sounds of it, the Perl script is an external tool your program
> can use and isn't incorporated in your program, and if you don't
> incorporate it in your program then the GPL has no effect on your
> program.

Quote:>Todd Knarr writes:
>> I think this is covered explicitly in the GPL: merely including a GPLed
>> program on the media with yours does not cause your program to be GPLed.

>Nothing can cause your program to be GPL'd except you GPL'ing it.

>> From the sounds of it, the Perl script is an external tool your program
>> can use and isn't incorporated in your program, and if you don't
>> incorporate it in your program then the GPL has no effect on your
>> program.

>Correct.

Thanks.
--
Jim Cochrane

Quote:> If I include the script in the same tar file or rpm file as my program and
> make that file available for downloading, does the GPL still have no effect
> on my program, or would that fit the definition of incorporating it into my
> program?

--
Collin was right. Never give a virus a missile launcher.
                                -- Erk, Reality Check #8