CString?

Grant Jacobs gjacobs at bioinfotools.com
Tue Apr 29 12:29:33 CEST 2003


Intuition tells me that CString is a 'C' string, as in the 
programming language 'C' (or a 'char *' if you want the C type 
definition). In C, these can be treated as either pointers or as 
character arrays (to cut a long story short). They are terminated 
with a \0  (if used correctly, that is: one of the "standard" buggy 
things to do in C is lose the terminating \0 which can cause all 
sorts of trouble. The Dest[size] := #0 example you gave is doing the 
"safe" thing of insisting that the string be terminated correctly.).

Its almost certainly compatible with Apple's CStringPtr = ^char ; as 
the point of these is C compatibility usually...

Usually characters are byte-sized in C. There are also wide 
characters, but that's another story again...

But we can want for Frank's definitive answer and the usual 
nitpicking of my sloppy answer :-|

Grant

At 6:32 AM +0000 29/4/03, Peter N Lewis wrote:
>Could someone explain o me what CString is in the RTS?
>
>It seems it is a pointer, and the docs somewhere describe it as 
>^Char, and it is generally used as a pointer, but some places it is 
>used as an array, as in   Dest[Size] := #0;
>
>Since there seems good support for CString in string.pas, I'm trying 
>to figure out if I can use it in the Mac Interfaces, if it is binary 
>compatible with the Mac's definition of CStringPtr = ^Char;
>
>BTW, I noticed in string.pas
>
>     if (s2 = nil) or (s2^ = #0)
>
>I know GPC defaults to always doing short circuit, but would that be 
>better written or_else?
>
>Thanks,
>    Peter.
>
>--
><http://www.interarchy.com/>  <http://documentation.interarchy.com/>


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