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<title>NEW operator</title>
<!-- Changed by: Martin Leslie, 14-Mar-1996 -->
<body bgcolor="#dddddd">
<font color=brown>
<hr>
<center><h1>NEW operator.</h1></center>
<hr>
<p>
The <b>new</b> operator replaces the
<a href="../../C/FUNCTIONS/malloc.html">malloc</a>
function provided in C to reserve storage taken from the heap.
<p>
The <b>new</b> operator requires one operand that describes the
type of data to be stored in the memory. Here are some examples.
<p>
<center>
<table bgcolor=ivory width="80%" border=1>
<tr>
<td>
<pre>
int *ptr1; // Declare a pointer to int.
ptr1 = new int; // Reserve storage and point to it.
float *ptr2 = new float; // Do it all in one statement.
delete ptr1; // Free the storage.
delete ptr2;
struct House // Declare a complex structure.
{
int Floors;
int Windows;
};
House *ptr3 = new House; // Reserve storage and point to it.
delete ptr3;
</pre>
</td>
</tr>
</table>
</center>
<p>
Blocks or arrays of storage can also be reserved as show in the
next example.
<p>
<center>
<table bgcolor=ivory width="80%" border=1>
<tr>
<td>
<pre>
char *ptr
ptr = new char[80];
delete [] ptr; // Free the storage.
</pre>
</td>
</tr>
</table>
</center>
<p>
Although <b>new</b> and
<a href="../../C/FUNCTIONS/malloc.html">malloc</a>
can be intermixed in the same code, it is probably best
to continue using
<a href="../../C/FUNCTIONS/malloc.html">malloc</a>
in existing code and <b>new</b> in new code. This is because
you can not use
<a href="delete.html">delete</a> with storage thats been
reserved with malloc and visa versa. If you keep to one
method or the other you are less likely to make a mistake.
<p>
<hr>
<h2>Examples:</h2>
<img src="../../GRAPHICS/computer.gif">
<a href="../EXAMPLES/new.cc">Example program.</a>
<hr>
<h2>See Also:</h2>
<img src="../../GRAPHICS/whiteball.gif">
<a href="delete.html">delete</a> keyword.
</font>
<hr>
<font color=black>
<h2>C References</h2>
<p>
<img src="../../GRAPHICS/whiteball.gif">
<a href="../../C/FUNCTIONS/malloc.html">malloc</a> function.
<p>
<img src="../../GRAPHICS/whiteball.gif">
<a href="../../C/FUNCTIONS/free.html">free</a> function.
</font>
<hr>
<p>
<center>
<table border=2 width="80%" bgcolor="ivory">
<tr align=center>
<td width="25%">
<a href="../cref.html">Top</a>
</td><td width="25%">
<a href="../../C/master_index.html">Master Index</a>
</td><td width="25%">
<a href="keywords.html">C++ Keywords</a>
</td><td width="25%">
<a href="../../C/FUNCTIONS/funcref.htm">Functions</a>
</td>
</tr>
</table>
</center>
<p>
<hr>
<font color=brown>
<address>Martin Leslie
17-Feb-96</address><p>
</font>
|
