You probably have the term linking in mind to draw the conclusion that if you're merely exec'ing an external binary, this exempts you from GPL restrictions. But

You probably have the term linking in mind to draw the conclusion that if you're merely exec'ing an external binary, this exempts you from GPL restrictions. But that term is used in the L(!)GPL to state an ok method of bundling your code along with the licensed lib. AFAIK, that GPL code is ok to bundle with proprietary software whenever GPL-ed code is invoked in a separate process, though heard frequently, has yet to stand in court, especially when said proprietary software is just a wrapper or web interface. Edit: IANAL