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<title>strtoul function</title>

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<h1>strtoul function </h1>
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<p>
<b>strtoul</b> will convert a string to an unsigned long integer. An important 
feature 
of this function is the ability to accept data in various number bases
and convert to decimal. If 
you are just working with decimal numbers,
<a href="atoi.html">atoi</a> is probably an easer function to use.
<hr>
<pre>
Library:   stdlib.h

Prototype: long int strtoul(const char *sptr, char **endptr, int base);

Syntax:	   char string1[]="ff";			/* string to convert	*/
	   int  base=16;			/* Base 16		*/
           unsigned long int ans;		/* Result		*/

           ans = strtoul(string, NULL, 16);
</pre>

<hr>
<h2>Notes</h2>
The first argument must not contain a + or -.<p>

The second argument (char **endptr) seems to be a waste of space! If 
it is set to NULL, STRTOL
seems to work its way down the string until it finds an invalid character
and then stops. All valid chars read are then converted if the string
starts with an invalid character the function returns ZERO (0).
<p>
The Third argument (base) can have a value of 0 or 2-32.
<ul>
<li>0 - strtol will attempt to pick the base. Only Dec, Oct Hex  supported.
<li>2-31 - The base to use.
</ul>
<hr> 
<h2>Examples</h2>
<img src=../../GRAPHICS/computer.gif>
<a href="../EXAMPLES/strtol.c"> example program</a> (actually the strtol example, but its near enough).<p>
<hr>
<h2>See also:</h2> 
<p>

<img src=../../GRAPHICS/whiteball.gif>
<a href="atoi.html">atoi</a> String to integer conversion.
<br>
<img src=../../GRAPHICS/whiteball.gif>
<a href="atof.html">atof</a> String to floating point conversion.
<br>
<img src=../../GRAPHICS/whiteball.gif>
<a href="atol.html">atol</a> String to long integer conversion.
<br>
<img src=../../GRAPHICS/whiteball.gif>
<a href="../MAN/strtod.htm">strtod</a> 
String to double conversion.
<br>
<img src=../../GRAPHICS/whiteball.gif>
<a href="strtol.html">strtol</a> String to long integer 
conversion.


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<address>Martin Leslie 
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