Re: Introductory Presentations, especially aimed at C++ programmers!

["Jeffrey R. Carter" <spam.jrcarter.not@spam.not.acm.org>]

On 12/09/2016 03:01 PM, Randy Brukardt wrote:
> "Paul Rubin" <no.email@nospam.invalid> wrote in message
> news:877f7b5llo.fsf@nightsong.com...
>>> exponentially better than being prevented from overflowing a buffer is
>>> being able to figure out how to do
>>> declare
>>>    B : Buffer (1 .. Just_The_Right_Size);
>>
>> Alternatively the buffer could be dynamically sized according to the
>> data.  That's not in the Ada spirit because of the possible OOM and
>> memory allocation latency getting in the way of embedded realtime
>> applications, but for a workstation app it's perfectly workable.
>> Horses for courses.
>
> That's one possible way to use the API in question, since there's no way to
> find out beforehand how much data you'll need. (You could ask for the size
> ahead of time, but of course that's a potential race condition so it doesn't
> really help.)

I was including in being able to do

declare
    B : Buffer (1 .. Just_The_Right_Size);

such things as

declare
    S : String := Get_Line;

and there's usually a way to do that even when you don't know beforehand how big 
the result will be. After all, the Get_Line function doesn't know beforehand how 
long a String it will return. I don't how the API in question works, so I can't 
say for sure if there's a way to do this for it, but there usually is.

-- 
Jeff Carter
"If you don't get the President of the United States on that
phone, ... you're going to have to answer to the Coca-Cola
Company."
Dr. Strangelove
32