On Wed, Jun 05, 2013 at 06:13:50AM -0600, Eric Blake wrote: > On 06/05/2013 03:10 AM, Colin Watson wrote: > > I've had multiple reports (https://savannah.nongnu.org/bugs/?36848, > > https://bugs.gentoo.org/show_bug.cgi?id=244517) telling me that FreeBSD > > is missing the clearenv function, even though it has setenv. It would > > be very helpful if Gnulib could handle this. Is "environ = NULL;" > > portable, or does it need something cleverer? > > clearenv() is non-standard (it is a glibc extension); but yes, glibc > documents that "environ = NULL" is a portable alternative.
Hm, that's not in my libc.info. Do you just mean the code? > And yes, it is probably quite easy to write a gnulib module that would > provide clearenv everywhere, although I fail to see why applications > need the overhead of a function call when an assignment would do. I was wary about other C libraries that might assume that the environ pointer can always be dereferenced; and e.g. http://hg.dovecot.org/dovecot-2.0/file/74d9f61e224d/src/lib/env-util.c#l56 has some specific portability notes which indicate that "environ = NULL" isn't an adequate replacement everywhere. This is the kind of reason I like to use Gnulib so that it can shield me from this nonsense, especially if somebody discovers another OS with some newer crazy requirement. :-) -- Colin Watson [cjwat...@debian.org]
