[gpsd-dev] EBADF in main select (Roy Barkas's bug)

[Eric S. Raymond]

A little research indicated that fcntl(fd, F_GETFL, 0) is about the
most lightweight to validate a file descriptor.  Accordingly, I have
added some recovery code to gpsd_await_input().

Roy, please test the head version.  You should no longer get "bad file
descriptor" and termination.

Ideally there's some cleanup actions that should be added, but that
would require a library verson bump of libgpsd - not the user-facing
API so probably OK, but I'd prefer to hold that until after 3.11.
-- 
                <a href="http://www.catb.org/~esr/";>Eric S. Raymond</a>

When all government ...in little as in great things... shall be drawn to
Washington as the center of all power; it will render powerless the checks
provided of one government on another, and will become as venal and oppressive
as the government from which we separated."     -- Thomas Jefferson, 1821