[ executive summary: trying to explain why static variable declarations within the body of functions is bad in kernel code. ] * Changli Gao (xiaosuo@xxxxxxxxx) wrote: > On Fri, Aug 20, 2010 at 12:11 AM, Mathieu Desnoyers > <mathieu.desnoyers@xxxxxxxxxx> wrote: > > > > Ah, I see. But I think the static variable should stay declared outside > > of the function scope, with a nice comment explaining why it's not > > initialized at init-time. > > > > Hiding global state in function code is usually frowned upon. > > > > I don't agree with you. We'd better not expose the variable which > isn't expected to be used by others. If not, maybe someone will misuse > it. We are talking about a static variable usable only within a single file, where is the problem ? A nice comment can have this effect. > The user should only reply on the interface, but not the internal > implementation. I'm talking about good practice to help code review. This is way more important than the potential "encapsulation" benefit of hiding global state (a static variable) within the body of a function. I remember that Andrew Morton has strong opinions about this, and I remember being in complete agreement with him on the topic. Thanks, Mathieu > > Thanks. > > -- > Regards, > Changli Gao(xiaosuo@xxxxxxxxx) -- Mathieu Desnoyers Operating System Efficiency R&D Consultant EfficiOS Inc. http://www.efficios.com -- To unsubscribe from this list: send the line "unsubscribe netfilter-devel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
