Re: [bug #46481] install-info can "corrupt" dir file if interrupted.

[Karl Berry]

    ag> of its new atomic file-swap ability:
    http://lists.gnu.org/archive/html/coreutils/2015-11/msg00068.html

Nice, but no "new" facility can be assumed for general use.  That's why
I hoped there would be a gnulib module that make use of such fancy new
facilities where possible, and fall back to whatever
best-possible-attempt otherwise.  To save Gavin the time, trouble, and
exposure of trying to implement it.  This is not a new problem.  One
would sure think it's been solved somewhere already in GNU and can be
reused.

    mthl> There is a big difference between the behavior expected at
    compile time and install time.

Oh, whatever.  Using gcc was just an example.  Same thing if I type
"make install" and hit CTRL-C (or CTRL-\ or kill -9 from another
terminal or unplugging the computer or whatever) in the middle of
installing some huge binary: I don't expect it to remain uncorrupted.
And, in practice, I believe that it is likely to get corrupted.

    You will want every installation operation to be
    atomic to garantee the integrity of the system.

Sure, I agree it is desirable, but I don't believe it is, in fact,
implemented by much of anything, except (I suppose) at the
package-manager level.

What's different about the dir file is that it amalgamates stuff from
many packages, and isn't easy to reconstruct (e.g., can't just type
"make install" again).  Thus I can see that in principle it is worth
extra trouble to try to preserve.  But I'm not volunteering to implement
it, so it's just an opinion ... -k