From: Eric Sunshine <sunshine@sunshineco.com>
Date: Mon, 03 Nov 2025 00:10:20 GMT
Subject: Re: [PATCH v2 3/3] parseopt: values of pathname type can be prefixed with :(optional)
Message-ID: <CAPig+cQLri3m9398R0JEf2fafKVkZBvOdxvpg=xPF2aZ6ayDvQ@mail.gmail.com>
In-Reply-To: <CALnO6CC=FFuMmBfJPzunUqDOBMBtmXm3i73y9M9LgRrhxzrs9g@mail.gmail.com>

On Sun, Nov 2, 2025 at 11:20 AM D. Ben Knoble
<ben.knoble+github@gmail.com> wrote:
> On Tue, Sep 30, 2025 at 11:26 AM Phillip Wood <phillip.wood123@gmail.com> wrote:
> > On 28/09/2025 22:29, D. Ben Knoble wrote:
> > > +             is_optional = skip_prefix(value, ":(optional)", &value);
> > > +             if (!value)
> > > +                     is_optional = 0;
> >
> > I'm struggling to see how value can be NULL here as we return early if
> > it NULL before calling skip_prefix()
>
> Doesn't the "skip_prefix" above write into value? So I think if
> "value" is exactly the string ":(optional)", then after the call to
> skip_prefix it points at the null terminator.

I haven't particularly been following this topic, but your response
suggests that you're reading the code as if it says:

    if (!*value)
        is_optional = 0;

whereas, Philip is reading the code as written, which lacks the `*` dereference.