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<title>The VOID keyword.</title>
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<center><h1>The VOID keyword.</h1></center>
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<p>
The <b>void</b> <a href="../glossary.html#keyword">keyword</a>
allows us to create functions that either do not require any
parameters or do not return a value.<p>
The following example shows a function that does not return
a value.
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<pre>
void Print_Square(int Number);
main()
{
Print_Square(10);
exit(0);
}
void Print_Square(int Number)
{
printf("%d squared is %d\n",Number, Number*Number);
}
</pre>
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<p>
The next example shows a function that does not require any parameters:
<p>
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<pre>
#include <stdlib.h>
#include <time.h>
int Random(void);
main()
{
printf("A random number is %d\n", Random());
exit(0);
}
int Random(void)
{
srand((unsigned int)time((time_t *)NULL));
return( rand());
}
</pre>
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<h2>Example:</h2>
<img src="../../GRAPHICS/computer.gif">
<a href="../EXAMPLES/pointer_func.c">void example</a>
<hr>
<h2>See also:</h2>
<img src="../../GRAPHICS/whiteball.gif">
<a href="../SYNTAX/functions.html">Functions</a>
<a href="../SYNTAX/functions.html#void">Void pointers</a>
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<address>Martin Leslie
</address><p>
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