command-line calls of GPL'd executables

[Paul Cody Johnston]

* phil hunt (philh at comuno.freeserve.co.uk) wrote:
>
>
> Consider this situation:
>
> Alice writes a program, aprog, which she licenses under the GPL.
>

First of all, don't assume my answer is correct, I've just begun to
get involved in these discussions, but it's something I think is
important.

> Bob writes another program, which invokes the aprog executable,
> using the POSIX system() call. Does Bob's program have to be
> released under a GPL-compatible license?

I don't think so.  This is not considered linking which I believe is
the criterion.

>
> (Assume for the sake of argument that there is no other program
> that does the same as aprog).
>
> What if aprog is, instead, licensed under the BSDL with advertising
> clause. Can be GPL his program?
>

Same thing I think.  In my opinion, sharing state between applications
does not complicate licensing issues.  If that were the case, then
every piece of software the uses TCP/IP or http could be considered
"the same program", and what a mess that would be.

Sharing code is another matter.  If the application shares
instructions, then the license is an issue.

But like most things when I open my trap prematurely, I'm wrong.

Paul

>
> --
> #===== Philip Hunt == philh at comuno.freeserve.co.uk ======#
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