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From: Peter Chapin <PChapin@vtc.vsc.edu>
Subject: Re: Troubles with C strings
Date: Sat, 26 Jul 2014 15:06:32 -0400
Date: 2014-07-26T15:06:32-04:00	[thread overview]
Message-ID: <3bOdnRP2NdykYU7ORVn_vwA@giganews.com> (raw)
In-Reply-To: <DCPAv.94175$46.4928@fx19.iad>

On 2014-07-26 11:15, Shark8 wrote:

> On 26-Jul-14 08:13, Victor Porton wrote:
>> Also: It seems that in Interfaces.C.Strings there is no function which
>> creates an Ada string of specified length from a chars_ptr (without
>> checking for NUL).
> 
> Such a function cannot exist: to determine the length of a C-style
> string you *must* scan through it for the terminating NULL. What you
> describe would be a "substring" method that can read beyond the
> string-bounds without raising an error... and I see no way that would
> end well.

Well the function could exist; it would just require an additional
parameter to specify how much should be copied. While such an approach
might be contrary to the sensibilities of Ada programmers, I don't think
C programmers would find it shocking.

Of course we are talking about an Ada interface here so adding a
function that by its nature could easily lead to undefined behave...
er... erroneous execution probably wouldn't be great.

  parent reply	other threads:[~2014-07-26 19:06 UTC|newest]

Thread overview: 8+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2014-07-26 14:13 Troubles with C strings Victor Porton
2014-07-26 15:15 ` Shark8
2014-07-26 15:52   ` Victor Porton
2014-07-26 17:09     ` Shark8
2014-07-26 19:06   ` Peter Chapin [this message]
2014-07-26 19:09     ` Victor Porton
2014-08-01 22:16       ` Victor Porton
2014-07-26 18:41 ` Niklas Holsti
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