Re: [PATCH/RFC 4/4] Add interactive mode to git-shell for user-friendliness

> * Kevin P. Fleming <kpfleming@digium.com> [100714 15:59]:
> > On 07/14/2010 04:04 AM, Ævar Arnfjörð Bjarmason wrote:
> > > On Wed, Jul 14, 2010 at 03:01, Greg Brockman <gdb@mit.edu> wrote:
> > >> +               execl(prog, prog, (char *) NULL);
> > >
> > > Why the casting of NULL? It's not done in the builtin/help.c code.
> > >
> > > Anyway, if it was cast it should be to (const char *), shouldn't it?
> >
> > When a NULL sentinel is passed to a varargs function that only
> > understands 'char *' arguments, the NULL must be cast specifically,
> > otherwise it will appear in the varargs array as an int or a long.
> 
> To be more specific: If NULL is (void *)0 then it does not need to be
> cast. Sadly the standard allows to define it as 0, and so it is on
> some systems. So to be portable it needs to be cast to be a pointer,
> otherwise the varargs argument is assumed to be an int.