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<title>strtol function</title>

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<h1>strtol function </h1>
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<p>
<b>strtol</b> will convert a string to a 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.
<p>
<hr>
<pre>

Library:   stdlib.h

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

Syntax:	   char     String[]="ff";		/* string to convert	*/
	   int      Base=16;			/* Base 16		*/
           long int Ans;			/* Result		*/

           Ans = strtol(String, NULL, Base);
</pre>

<hr>
<h2>Notes</h2>
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>
<p>
<hr>
<dt><h2>See also:</h2> 
<p>
<dt><a href="atoi.html">atoi</a> String to integer conversion.
<dt><a href="atof.html">atof</a> String to floating point conversion.
<dt><a href="atol.html">atol</a> String to long integer conversion.
<dt><a href="../MAN/strtod.htm">strtod</a> String to double conversion.
<dt><a href="strtoul.html">strtoul</a> String to unsigned long integer 
conversion.
<dt><a href="../MISC/numconv.html">Conversion table.</a>
<p>


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<address>Martin Leslie 
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