2(c) If the modified program normally reads commands interactively
when run, you must cause it, when started running for such interactive
use in the most ordinary way, to print or display an announcement
including an appropriate copyright notice and a notice that there is
no warranty (or else, saying that you provide a warranty) and that
users may redistribute the program under these conditions, and telling
the user how to view a copy of this License. (Exception: if the
Program itself is interactive but does not normally print such an
announcement, your work based on the Program is not required to print
an announcement.)
This has two parts, which I will discuss separately below. However,
they do share some things in common: The wording is not fixed (at least
by the license[1]); you can word it however you'd like. It is only
required if the program 'reads commands interactively'. And lastly,
they are both small. If any of these weren't the case, I don't think
there would be much argument to its freeness.
First, the copyright notice. I find this to be a fairly reasonable
requirement due to Title 17 USC 401(c), which states (in part) "[t]he
notice shall be affixed to the copies in such manner and location as to
give reasonable notice of the claim of copyright." 401(d) specifies
that if the notice is properly given then a defendant may not claim
innocent infringement to mitigate damages. Especially after reading the
copyright office's regulations on what constitute appropriate notice
(see [0]) I believe that for an interactive work, the is quite
reasonable. ([0] lists displaying it at login, for example.) I thus
feel that this is a legal requirement for the copyright holder to claim
his rights under law, thus on the free side of the line.
Second, comes the warranty notice. I think Sec. 2-316 of the Uniform
Commercial Code[2] covers this: "...to exclude or modify the implied
warranty of merchantability or any part of it the language must mention
merchantability and in case of a writing must be conspicuous, and to
exclude or modify any implied warranty of fitness the exclusion must be
by a writing and conspicuous." So this looks like the FSF is just
making sure they are suitably conspicuous about their lack of warranty.
Remember, in general, people otherwise wouldn't know that the software
is "as is"; one of the great things about free software is you don't
have to "agree" to a damned EULA. Once again, I think this is a quite
reasonable thing to require reasonably, and (again) on the free side of
the line.
So, in summary, even without DFSG 10, I find GPL 2(c) free.
[0] Look for 201.20 at <http://copyright.gov/title37/201/index.html>.
[1] 'appropriate copyright notice' is defined by law. e.g., 17 USC 401.
[2] I found a copy on the web; <http://tinyurl.com/2c5mq>. No idea if
that
is a session-based link though.