From:	Hans-Bernhard Broeker <broeker AT physik DOT rwth-aachen DOT de>
Newsgroups:	comp.os.msdos.djgpp
Subject:	Re: a bit about arrays...
Date:	10 Aug 2000 14:34:59 GMT
Organization:	Aachen University of Technology (RWTH)
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Vermin <ratspl AT hotmail DOT com> wrote:

> <1>
> What's the difference between

> char anArray[100];

> and

> char *anArray;
> anArray = new (char)[100];

Place of storage, and lifetime of the array. The first creates an
array that lives on the stack, until you leave the block the
definition is found in (or in a global data segment until program
termination, if it's at file scope), the second creates a block that
exists until you delete[] it, and a pointer to it with a certain
lifetime.

> <2> How can I pass an array with undefined size to a procedure, and
> get the procedure to set the array size (C++)??

You can't. Array size isn't modifiable a posteriori. You can only
change the size of "new"ed arrays, and that only by delete[]ing them
and "new"ing a new one.

If you need a truly variable-sized array, look up the 'vector' template.


-- 
Hans-Bernhard Broeker (broeker AT physik DOT rwth-aachen DOT de)
Even if all the snow were burnt, ashes would remain.

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