question about env and function malloc

[Rich Felker]

On Mon, Dec 22, 2014 at 04:29:17PM -0200, Alexandre Oliva wrote:
> On Dec 19, 2014, Rich Felker <dalias@libc.org> wrote:
> 
> > On Thu, Dec 18, 2014 at 03:44:10AM -0200, Alexandre Oliva wrote:
> >> [Cc:ing the list]
> >> 
> >> On Dec 17, 2014, MaShimiao <mashimiao.fnst@cn.fujitsu.com> wrote:
> >> 
> >> > But, the description of env in glibc manual says if a function accesses 
> >> > environment with getenv() of similar, without any guard, then it should be
> >> > marked with env. it doesn't mention any special functions.
> >> > Do you think we should add some words to remind users that there are some special
> >> > conditions in which even a function calls getenv(), it will not be marked with env.
> >> > Just like malloc() or free().
> >> > Or we just add explanations in the description of each special functions?
> >> 
> >> I think a note at the exception point should be enough, as in the patch
> >> below.
> 
> > This is a conformance issue; for the purpose of safety with respect to
> > modifying the environment in a multi-threaded program, the set of
> > standard functions allowed to access the environment is fixed by POSIX
> > and does not include malloc.
> 
> The “env” safety note quite often indicate deviations from the standard
> anyway, so I don't see what light your statement sheds on the issue at
> hand.  Can you please elaborate?  TIA,

OK, if this is a known issue that's being left for later, then my
comment doesn't really add anything.

Rich